The 22-year-old has come under criticism in recent weeks after being caught on camera smoking during an off-season holiday in Las Vegas.
Wilshere was limited to 24 Premier Legue appearances last season after the England international was forced to contend with a string of injuries.
However, Arsenal manager Wenger feels Wilshere is in the best shape that the midfielder has ever been ahead of the new Premier League season.
“It’s a big season for Jack but he’s in the best shape that he’s been for three years,” Wenger said.
“He has prepared and he has got over his ankle problems. I think that he will have a great season but it’s a very important season for him.”
Earlier this week, former Manchester United midfielder Paul Scholes, who was previously critical of the midfielder, tipped Wilshere to come of age over the course of the 2014/15 campaign.
“I always seem to upset people whenever I say anything. I don’t mean to, honestly!” Scholes told talkSPORT.
“I played against Jack at 17 and thought what a player we’ve got here. And I don’t feel he’s gone to the next level yet. But you have to remember he’s had horrendous injury problems with his ankle and I’m sure the best is still to come from Jack. I hope so anyway because he’s an English midfield player and I want him to do well.
“And he’s playing for a good team at Arsenal as well. I think they could have a good season, especially if Aaron Ramsey stays fit, and they’ve made a great signing in Alexis Sanchez. So hopefully this is the year when Jack really comes of age.”
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