The Predators are trying to make the playoffs for the first time in franchise history.
They sent a fourth-round pick in the 2003 draft to Montreal for Petrov, 31, a right wing, who has seven goals and 16 assists in 53 games this season. He had a career-high 24 goals in 2001-02.
While Petrov has struggled this season, General Manager David Poile acquired him for his speed and skill. He should fit in nicely a with a young team that has outscored opponents, 21-6, during a four-game winning streak.
"He is also a veteran player who has been involved in the playoff hunt before," Poile said. "And his presence gives the team greater depth and gives the coaches more flexibility with the lineup."
Petrov, a ninth-round pick in the 1991 draft, has 70 goals and 113 assists in 365 NHL games, all with Montreal. He has one goal and six assists in 20 playoff games.
The Russian is expected to join Nashville for its game in St. Louis on Tuesday night.
The deal also came two days after center David Legwand, the team's leading scorer, suffered a broken collarbone that will sideline him four to six weeks.
The Predators still have 11 pick in the first four rounds of the June NHL Draft, which will be held at the Gaylord Entertainment Center in Nashville.
While the Canadiens are four points out of the eighth and final playoff berth in the Eastern Conference, the Predators are three back in the West. They have won eight of their last nine games (8
The Predators missed the playoffs in each of their first four NHL seasons.