The Selke Trophy winner as the league's best defensive forward had successful hip labral surgery and is expected to make a full recovery in 10-12 weeks, the team said.
"After consultation with our team physicians following the playoffs, it was deemed that Ryan would require a procedure on his hip," Canucks General Manager Mike Gillis said.
"We expect a full recovery and determined this procedure would best serve both Ryan and the team's long term goals."
Kesler scored a career-high 41 goals and had 73 points in 82 games last season for a Canucks team that finished with the league's top record in the regular season.
He added seven goals and 12 assists in 25 playoff games for a Vancouver team that lost to the Boston Bruins in the Stanley Cup finals.
The Canucks open their regular season October 6 against the Pittsburgh Penguins. If Kesler needs a full 12 weeks to recover he could return for the team's ninth game of the season against Edmonton on October 25.