Adam Thomas Kennedy (born January 10, 1976) is an American Major League Baseball second baseman for the Seattle Mariners. He previously played for the Oakland Athletics, the Los Angeles Angels of Anaheim, and had two stints with the St. Louis Cardinals. He was also signed to a minor league deal with the Tampa Bay Rays organization in 2009, but never played for the Rays themselves. He signed with the Nationals on February 5, 2010. Terms of the deal were not disclosed. Kennedy began the 2010 season as a bench player, but he became the Nationals' regular second baseman after they traded Cristian Guzmán to the Texas Rangers on July 30, 2010.

Kennedy attended J.W. North High School in Riverside, California, playing baseball and basketball. He is the son of Tom Kennedy, who teaches Health at North High School.

Adam Kennedy attended Cal State Northridge, where he played shortstop for the Matador baseball squad. He set school records in career hits, RBI and batting average and was a three-time All American. He led the nation in hits as a sophomore and junior.