Hardy, 26, batted .283 with 24 home runs and 74 RBIs in 146 games last season and helped the Brewers win the National League Wild Card.
Hardy, who made $2.65 million last year, is the third player in club history to hit 20 or more home runs in two separate seasons as a shortstop, joining Robin Yount and Jose Hernandez.
The Brewers still have five players who are arbitration eligible: pitchers Dave Bush and Seth McClung, first baseman Prince Fielder, outfielder Corey Hart and second baseman Rickie Weeks.
Fielder and Hart are eligible for the first time.
Hopefully the next step for the Brewers will be signing Hardy to a long-term contract.