Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the use in this Registration Statement on Form F-1 of our report dated July 6, 2021 relating to the financial statements of Algoma Steel Group Inc. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ Deloitte LLP

Chartered Professional Accountants

Licensed Public Accountants

Toronto, Canada

October 27, 2021