The Grizzlies announced the signing Wednesday. Terms weren't disclosed.
Memphis had acquired Ennis and Mario Chalmers from Miami in a Nov. 10 trade that sent guard Beno Udrih and forward Jarnell Stokes to the Heat. After the Grizzlies waived Ennis in March, he finished the season with New Orleans. In his nine games with the Pelicans, he averaged 15.9 points, 3.9 rebounds, 2.0 assists and 31.3 minutes per game.
The 26-year-old has played a total of 84 regular-season NBA games.