The 33-year-old Clement, who last pitched in 2006 for the Boston Red Sox, sat out much of that season and all of 2007 because of an injury to his pitching shoulder. He underwent arthroscopic surgery Sept. 26, 2006.
Clement's record in nine seasons is 87-86. He has also pitched for the San Diego Padres, Florida Martins and Chicago Cubs.
"Matt is a very talented pitcher who has been beset by injury the last few years," Cards' General Manager John Mozeliak said Thursday.
"Based on our findings from his rehabilitation last season and his recent physical, we feel that he can be a solid addition to our starting rotation and should have no limitations upon reporting to spring training."