Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the Registration Statement on Form S-8 of our reports dated April 10, 2026, relating to the financial statements of Canadian Solar Inc. and subsidiaries (the “Company”), and the effectiveness of the Company’s internal control over financial reporting, appearing in the Annual Report on Form 20-F of Canadian Solar Inc. for the year ended December 31, 2025.

/s/ Deloitte Touche Tohmatsu Certified Public Accountants LLP

Shanghai, China

September 21, 2026