Josef Antonín Štěpán or Joseph Anton Steffan (c. March 1726 – c. April 1797) was a Bohemian classical era composer and harpsichordist.

Steffan was born in Kopidlno, Hradec Králové Region, Bohemia in March 1726, the son of a schoolmaster and church organist. In 1741 he fled from the Prussian army to Vienna. He received his first musical lessons from his father but, in Vienna, he studied with Schilck and later became a student of Georg Christoph Wagenseil. He became the piano teacher of Maria Carolina and Marie Antoinette. In 1775, he contracted an eye disease which left him almost blind. He gave up his position at the court, but continued to compose. He died in Vienna in April 1797.