Wilshere, 20, has been out since suffering an ankle problem during the 2011 Emirates Cup pre-season tournament, and also had minor knee surgery in May this year.
The midfielder is training with the first-team again though and is set to feature for the club's under-21 side away against West Brom on Monday afternoon.
England have World Cup qualifying matches next month against San Marino at Wembley and then in Poland.
However Arsenal manager Wenger warned against expecting an immediate return at international level for the 20-year-old who was left devastated at having to sit out Euro 2012.
"Jack will play on Monday, he will play his first game with the under-21s, maybe an hour or something like that," said Wenger, whose side host Chelsea on Saturday having thumped Coventry 6-1 on Wednesday to reach the fourth round of the Capital One Cup.
"It is another important step, but he has not played for 14 months so we have to calm your [the media's] impatience a little bit.
"It is fantastic for him. When you are at that age and are out for such a long time, it is absolutely massive to take (for) him and (Emmanuel) Frimpong to come back and (massive) for us as well."
When pressed on the prospect of Wilshere featuring for Roy Hodgson's England team in October, the Arsenal manager urged caution.
He said: "I think that will be too early for him. He has not played for 14 months."
Wenger then joked: "Who does England play, San Marino? I think he can play in that game!"
Frimpong, 20, made his own long-awaited return to action on Wednesday night, coming on as a substitute to end seven months out after rupturing the anterior cruciate ligament in his right knee while on loan at Wolves during February.
It was a second potential career-ending injury for the Ghana-born midfielder, who suffered a similar problem in his left knee two years ago.
Frimpong said on Arsenal Player: "It feels good to be back after so much hard work in the gym, and I am just pleased to be playing football again.
"I am a footballer, all I want to do is get out there and help my team, whether I am fit enough to play or fit enough to be in the squad.
"I just want to be out there with the lads and helping Arsenal progress."
Frimpong relished heading full-on into the physical challenges again.
"It is quite important when you come back from a big injury. You want people to knock you about a bit. I got one, but I wanted more," he said.
Theo Walcott scored twice against Coventry to stake his claim for a recall to the starting XI in the Barclays Premier League this weekend.
Captain Thomas Vermaelen will be in contention, having recovered from flu, but goalkeeper Wojciech Szczesny remains sidelined by an ankle problem.