"I'm happy right now," Montero said. "I didn't want to have to go to arbitration."
Montero hit .266 with 20 doubles, nine home runs and 43 RBIs in 2010, a season in which he was limited to 85 games after undergoing surgery to repair a torn meniscus in his right knee in April.
For the last few weeks, Montero has been working with a personal trainer in Florida.
"My knee feels great," he said. "I'm still working and getting in better and better shape."
Montero had a breakout season in 2009, when he took over the starting catching role from Chris Snyder and went on to hit .294 with 16 home runs and 59 RBIs in 128 games.
Toward the end of last season, he admitted he was disappointed in his performance and expected bigger things from himself in 2011.
Wednesday, he sounded optimistic about his team's chances of improving after back-to-back last-place finishes in the National League West. The D-backs have added a number of veterans via free agency, including backup catcher Henry Blanco.
"I think we've got a good team," Montero said. "Henry Blanco is a really good addition because he's going to help me. He's a great guy to be around and to learn from."