At the start of December, Wenger had failed to select Wilshere from the opening whistle in any top-flight fixture this season, but the 25-year-old has completed 90 minutes in three matches played since December 13, including the 3-3 draw with Liverpool on Friday night.
Wilshere has been plagued with injury problems throughout his career, but Wenger feels that the England international is as fit as he has been in a number of years.
The Frenchman is quoted by Sky Sports News as saying: "He's better now than he was in the last two or three years.
"I think he is positive overall and is in a very good shape at the moment."
Wilshere has just six months remaining on his contract at the Emirates Stadium, with Wenger insisting that the player must prove his fitness before talks over a new deal can get underway.