Stephen John Riordan (24 December 1876 – 23 August 1942) was an Irish hurler who played for Cork Championship club Blackrock.
He played for the Cork senior hurling team for six years, during which time he usually lined out as a half-forward.
Riordan began his hurling career at club level with Blackrock.
He broke onto the club's top adult team in 1898, a year in which he won his first Cork Championship title.
From his debut, he was ever-present as a half-forward and made 21 Championship appearances in a career that ended with his last game in 1908.