Ozuna, who helped the Cardinals beat the Braves in the playoffs last October, signed a one-year contract worth $18 million, according to the club. The Braves now have 40 players on the team's 40-man roster.
Ozuna posted a .429 average with two home runs for the Cardinals in their five-game victory over the Braves in the National League Division Series last year.
The two-time All-Star choice spent his first five seasons with the Miami Marlins before he was traded to the Cardinals. He spent two seasons in St. Louis, recording a .241 average with 29 home runs and 89 RBIs in 2019.
In 932 career games between the Marlins and Cardinals, Ozuna has a .272 average with 148 homers and 538 RBIs. He had a career-high 12 stolen bases with the Cardinals last season.