The 41-year-old Ramirez hit .259 with three home runs and 13 RBIs in 30 games for Triple-A Round Rock after agreeing to a deal early last month. He hit all of the homers in the first eight games.
Rangers general manager Jon Daniels said Tuesday that Ramirez was released so he could pursue other opportunities if he chooses.
Daniels said, based on the team's evaluation, there wasn't a spot on the Rangers roster for Ramirez.
The 12-time All-Star is a .312 career hitter, and is 14th on the career home runs list with 555. He started out the season playing in Taiwan.