Ramirez will sign a three-year contract with the Brewers, pending the completion of a physical.
The deal is expected to be in the $34 to $37 million range, according to FOX Sports.
The 33-year-old free agent would add some much needed power to Milwaukee's lineup, particularly if the team is unable to re-sign star first baseman Prince Fielder, and with reigning MVP Ryan Braun facing a possible 50-game suspension for failing a drug test.
Ramirez has hit over .300 five times in little more than eight seasons in Chicago. The two-time All-Star hit .306 this season with 26 home runs and 93 RBIs. He is a .284 hitter lifetime with 315 home runs in 14 seasons.