Radek Štěpánek (born 27 November 1978 in Karviná) (Czech pronunciation: ) is a professional tennis player from the Czech Republic.

Štěpánek turned professional in 1996. He started on tour as a doubles specialist, winning 12 ATP titles. Since 2002, Štěpánek has focused on being a better singles player while still playing top-level doubles. He is known for his after the shot grunting, his over the top celebrations and his many relationships with WTA players.

2006 was Štěpánek's best year to date, he found himself on the verge of getting into the top ten of ATP rankings, as he defeated José Acasuso in the semi-finals of the Masters Series event in Hamburg. He went on to lose the final in straight sets against Spain's Tommy Robredo. At that point, he achieved a career-high ATP world ranking of No. 11 in singles.