Telos (TLS) S-1MEF Registration of additional securities for an S-1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

Telos Corporation

19886 Ashburn Road

Ashburn, Virginia 20147

We hereby consent to the incorporation by reference in this Registration Statement on Form S-1 of our report dated April 10, 2020, except for the effects of disclosing earnings per share information discussed in Note 1, as to which the date is October 6, 2020, and except for the effects of the stock split discussed in Note 1, as to which the date is November 16, 2020 relating to the consolidated financial statements of Telos Corporation, which is included in that the Company's Registration Statement on Form S-1 (No. 333-249334).

We also consent to the reference to us under the caption “Experts” in the Reigistration Statement on Form S-1 (No. 333-249334) incorporated by reference in this Registration Statement.

/s/ BDO USA, LLP

McLean, Virginia

November 19, 2020