Donald A. (Tony) Martin (born 24 December 1940) is a set theorist and philosopher of mathematics at UCLA, where he is a member of the faculty of mathematics and philosophy.
Among Martin's most notable work are the proofs of analytic determinacy (from the existence of a measurable cardinal), Borel determinacy (from ZFC alone), the proof (with John R. Steel) of projective determinacy (from suitable large cardinal axioms), and his work on Martin's axiom.
Martin is a Harvard junior fellow.