Exhibit 5.1

		750 E. PRATT STREET SUITE 900 BALTIMORE, MD 21202 T 410.244.7400 F 410.244.7742 www.Venable.com

December 22, 2025

PennyMac Mortgage Investment Trust

3043 Townsgate Road

Westlake Village, California 91361

Ladies and Gentlemen:

We have served as Maryland counsel to PennyMac Mortgage Investment Trust, a Maryland real estate investment trust (the “Company”), in connection with certain matters of Maryland law arising out of the registration by the Company and PennyMac Corp., a Delaware corporation (“PMC”), on a Registration Statement on Form S-3, Commission File Nos. 333-280211 and 333-280211-1, as amended by Post-Effective Amendment No. 1 thereto (the “Registration Statement”), filed by the Company and PMC with the United States Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”) of (i) the sale and issuance by PMC of $75,000,000 aggregate principal amount of 8.500% Exchangeable Senior Notes due 2029 (the “Notes”) in a direct purchase transaction covered the above referenced Registration Statement and (ii) the guarantee (the “Guarantee”) of the Notes and the issuance of the Exchange Shares (as defined below) by the Company.

In connection with our representation of the Company, and as a basis for the opinion hereinafter set forth, we have examined originals, or copies certified or otherwise identified to our satisfaction, of the following documents (hereinafter collectively referred to as the “Documents”):

1. The Registration Statement and the related form of prospectus included therein, in substantially the forms in which they were transmitted to the Commission for filing under the Securities Act;

2. The Company’s Prospectus, dated June 14, 2024, as supplemented by the Prospectus Supplement, dated December 18, 2025, relating to the offering and sale of the Notes, each in the form filed with the Commission pursuant to Rule 424(b) of the General Rules and Regulations promulgated under the Securities Act;

3. The declaration of trust of the Company (the “Declaration”), certified by the State Department of Assessments and Taxation of Maryland (the “SDAT”);

4. The Second Amended and Restated Bylaws of the Company, certified as of the date hereof by an officer of the Company; 5. A certificate of the SDAT as to the good standing of the Company, dated as of a recent date;

PennyMac Mortgage Investment Trust

December 22, 2025

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6. Resolutions (the “Resolutions”) adopted by the Board of Trustees of the Company, and a duly authorized committee thereof, relating to, among other matters: (i) the authorization of the execution, delivery and performance by the Company of the Indenture (as defined below) and Global Note (as defined below) and (ii) the issuance of the Guarantee and the Exchange Shares, certified as of the date hereof by an officer of the Company;

7. The Global Note evidencing the Notes, dated as of the date hereof (the “Global Note”), registered in the name of Cede & Co., as nominee for The Depositary Trust Company, representing the Notes;

8. The Indenture, dated as April 30, 2013 (the “Base Indenture”), by and among the Company, PMC and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”), as supplemented by the Fourth Supplemental Indenture, dated as of May 24, 2024 (the “Supplemental Indenture” and, together with the Base Indenture, the “Indenture”), among the Company, PMC and the Trustee;

9. A certificate executed by an officer of the Company, dated as of the date hereof; and

10. Such other documents and matters as we have deemed necessary or appropriate to express the opinion set forth below, subject to the assumptions, limitations and qualifications stated herein.

In expressing the opinion set forth below, we have assumed the following:

1. Each individual executing any of the Documents, whether on behalf of such individual or another person, is legally competent to do so.

2. Each individual executing any of the Documents on behalf of a party (other than the Company) is duly authorized to do so.

3. Each of the parties (other than the Company) executing any of the Documents has duly and validly executed and delivered each of the Documents to which such party is a signatory, and such party’s obligations set forth therein are legal, valid and binding and are enforceable in accordance with all stated terms.

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December 22, 2025

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4. All Documents submitted to us as originals are authentic. The form and content of all Documents submitted to us as unexecuted drafts do not differ in any respect relevant to this opinion from the form and content of such Documents as executed and delivered. All Documents submitted to us as certified or photostatic copies conform to the original documents. All signatures on all Documents are genuine. All public records reviewed or relied upon by us or on our behalf are true and complete. All representations, warranties, statements and information contained in the Documents are true and complete. There has been no oral or written modification of or amendment to any of the Documents, and there has been no waiver of any provision of any of the Documents, by action or omission of the parties or otherwise.

5. Upon the issuance of any of common shares of beneficial interest, $0.01 par value per share (the “Common Shares”), upon exchange of the Notes (the “Exchange Shares”), the total number of Common Shares issued and outstanding will not exceed the total number of Common Shares that the Company is then authorized to issue under the Declaration.

6. None of the Exchange Shares will be issued or transferred in violation of any restriction or limitation contained in Article VII of the Declaration.

Based upon the foregoing, and subject to the assumptions, limitations and qualifications stated herein, it is our opinion that:

1. The Company is a real estate investment trust duly formed and validly existing under and by virtue of the laws of the State of Maryland and is in good standing with the SDAT.

2. The execution and delivery of the Indenture and the Global Note by the Company have been duly authorized, and the Indenture and the Global Note have been duly executed and delivered by the Company. The issuance of the Guarantee has been duly authorized.

3. The issuance of Exchange Shares has been duly authorized by all necessary trust action and, if and when issued and delivered by the Company upon exchange of the Notes in accordance with the terms of the Notes and the Indenture, the Exchange Shares will be validly issued, fully paid and nonassessable.

The foregoing opinion is limited to the laws of the State of Maryland and we do not express any opinion herein concerning U.S. federal law or the laws of any other state. We express no opinion as to the applicability or effect of any federal or state securities laws, including the securities laws of the State of Maryland, or as to federal or state laws regarding fraudulent transfers. To the extent that any matter as to which our opinion is expressed herein would be governed by the laws of any jurisdiction other than the State of Maryland, we do not express any opinion on such matter. The opinion expressed herein is subject to the effect of any judicial decision which may permit the introduction of parol evidence to modify the terms or the interpretation of agreements.

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December 22, 2025

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The opinion expressed herein is limited to the matters specifically set forth herein and no other opinion shall be inferred beyond the matters expressly stated. We assume no obligation to supplement this opinion if any applicable law changes after the date hereof or if we become aware of any fact that might change the opinion expressed herein after the date hereof.

This opinion is being furnished to you for submission to the Commission as an exhibit to the Company’s Current Report on Form 8-K relating to the issuance of the Notes (the “Current Report”). We hereby consent to the filing of this opinion as an exhibit to the Current Report and to the use of the name of our firm therein. In giving this consent, we do not admit that we are within the category of persons whose consent is required by Section 7 of the Securities Act.

Exhibit 5.2

December 22, 2025

PennyMac Mortgage Investment Trust

PennyMac Corp.

3043 Townsgate Road

Westlake Village, California 91361

Ladies and Gentlemen:

We refer to the Registration Statement on Form S-3 (File Nos. 333-280211 and 333-280211-01), initially filed by PennyMac Mortgage Investment Trust, a Maryland real estate investment trust (the “Company”), and PennyMac Corp., a Delaware corporation and an indirect wholly-owned subsidiary of the Company (the “Issuer”), with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”), on June 14, 2024, as amended by Post-Effective Amendment No. 1 thereto, filed with the SEC on December 11, 2025 (as so filed and amended, the “Registration Statement”), which Registration Statement became effective upon filing pursuant to Rule 462(e) under the Securities Act. Pursuant to the Registration Statement and the securities purchase agreement, dated December 18, 2025 (the “Purchase Agreement”), among the Issuer, the Company and the investor named therein, the Issuer is issuing $75,000,000 aggregate principal amount of its 8.500% Exchangeable Senior Notes due 2029 (the “Notes”). The Notes are being issued under an Indenture, dated as of April 30, 2013 (the “Base Indenture”), among the Issuer, as issuer, the Company, as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”), as supplemented by the Fourth Supplemental Indenture thereto, dated as of May 24, 2024 (the “Fourth Supplemental Indenture” and, together with the Base Indenture, the “Indenture”) and an Officers’ Certificate, dated December 22, 2025, pursuant thereto. The obligations of the Issuer under the Notes will be fully and unconditionally guaranteed by the Company (the “Guarantee” and, together with the Notes, the “Securities”).

This opinion letter is being delivered in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

We have examined the Registration Statement, the Indenture, the Purchase Agreement, the Securities in global form and the resolutions adopted by the board of directors of the Issuer, the board of trustees of the Company, and the respective pricing committees established by such boards relating to the Registration Statement, the Indenture, the Purchase Agreement and the issuance of the Securities. We have also examined originals, or copies of originals certified to our satisfaction, of such agreements, documents, certificates and statements of the Issuer and the

Sidley Austin (NY) LLP is a Delaware limited liability partnership doing business as Sidley Austin LLP and practicing in affiliation with other Sidley Austin partnerships.

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PennyMac Corp.

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Company and other corporate documents and instruments, and have examined such questions of law, as we have considered relevant and necessary as a basis for this opinion letter. We have assumed the authenticity of all documents submitted to us as originals, the genuineness of all signatures, the legal capacity of all persons and the conformity with the original documents of any copies thereof submitted to us for examination. As to facts relevant to the opinions expressed herein, we have relied without independent investigation or verification upon, and assumed the accuracy and completeness of, certificates, letters and oral and written statements and representations of public officials and officers and other representatives of the Issuer and the Company.

Based on and subject to the foregoing and the other limitations, qualifications and assumptions set forth herein, we are of the opinion that:

1. The Notes have been duly authorized by the Issuer. When the Notes have been duly executed and delivered by the Issuer and duly authenticated and delivered by the Trustee pursuant to the provisions of the Indenture against payment of the requisite consideration therefor as provided in the Purchase Agreement, the Notes will constitute valid and binding obligations of the Issuer.

2. When the Guarantee has been duly authorized, executed and delivered by the Company, and when the Notes have been duly authorized, executed and delivered by the Issuer and duly authenticated and delivered by the Trustee pursuant to the provisions of the Indenture against payment of the requisite consideration therefor as provided in the Purchase Agreement, the Guarantee will constitute a valid and binding obligation of the Company.

Our opinions are subject to bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance, fraudulent transfer and other similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether considered in a proceeding in equity or at law), including concepts of commercial reasonableness, good faith and fair dealing and the possible unavailability of specific performance or injunctive relief. Our opinions are also subject to (i) provisions of law which may require that a judgment for money damages rendered by a court in the United States of America be expressed only in United States dollars, (ii) requirements that a claim with respect to any debt securities or other obligations that are denominated or payable other than in United States dollars (or a judgment denominated or payable other than in United States dollars in respect of such claim) be converted into United States dollars at a rate of exchange prevailing on a date determined pursuant to applicable law and (iii) governmental authority to limit, delay or prohibit the making of payments outside of the United States of America or in a foreign currency.

This opinion letter is limited to the Delaware General Corporation Law and the laws of the State of New York (excluding the securities laws, the blue sky laws, the real estate syndication laws or the municipal laws or the laws, rules or regulations of any local agencies or governmental authorities of or within the State of New York). Various issues pertaining to Maryland law are addressed in the opinion of Venable LLP, which has been separately provided to you.

PennyMac Mortgage Investment Trust

PennyMac Corp.

December 22, 2025

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We express no opinion with respect to those matters herein, and to the extent elements of those opinions are necessary to the conclusions expressed herein, we have, with your consent, assumed such matters. We express no opinion as to the laws, rules or regulations of any other jurisdiction, including, without limitation, the federal laws of the United States of America or any state securities or blue sky laws.

We hereby consent to the filing of this opinion letter as an exhibit to the Company’s Current Report on Form 8-K filed on December 22, 2025 and the incorporation by reference of this opinion letter as an exhibit to the Registration Statement and to all references to our Firm under the caption “Legal Matters” in the prospectus constituting part of the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.