Yusmeiro Alberto Petit (born November 22, 1984, in Maracaibo, Venezuela) is a pitcher in Major League Baseball who plays for the Arizona Diamondbacks. Petit bats and throws right-handed.
Petit was originally signed by the New York Mets as an undrafted free agent on November 15, 2001. He was ranked as the 46th-best prospect by Baseball America in 2005 and the 69th prospect in 2006. Baseball America also named him the best pitcher in the Mets minor league system in 2006.
On November 24, 2005, Petit was traded to the Florida Marlins, along with first baseman Mike Jacobs and infielder Grant Psomas, for first baseman Carlos Delgado. He played in 15 games for the Marlins in 2005, starting one game. He went 1-1 with a 9.57 earned run average.