Heskey, who has been linked with a move to former club Leicester, will return to the Villa squad for Sunday's FA Cup clash at Arsenal after a spell on the sidelines with an Achilles problem.
The current contract of the former England player runs out in May and only then will McLeish weigh up the possible options.
McLeish said: "We realise that this is a transitional period at the club so it is not right for us to make any quick decisions. The overall position is that we'll review things at the end of the season.
"It's up to guys like big Emile to produce a few good performances between now and the end of the season by banging in a few goals, getting a few assists, and then we can address it at that time.
"From what I've seen in training this morning, I would certainly say he will continue to give everything. Emile is a guy who gives everything and does everything he can for the team.
"Will he go back to Leicester in the summer? I haven't got a clue."
Heskey continued to make himself available for selection despite the Achilles setback until it became too serious to continue.
McLeish said: "We've just been kind of managing him and allowing him to make an impact as a sub or for a certain amount of time in games.
"It just became a bit intolerable for him but he's had a few scans and injections. He's fit to play."
McLeish will look for on-loan Los Angeles Galaxy striker Robbie Keane to continue the form which brought him two goals on his full debut at Wolves.
He also created a favourable impression when Gordon Strachan, his former manager at Coventry, was invited by former Aberdeen and Scotland team-mate McLeish to watch Villa train this week.
He said: "I had Gordon in this week for lunch and to observe training and he said Robbie was making the same kind of movement he does now at the age of 20 at Coventry.
"Gordon said he had been trying to teach that to other strikers at Coventry like Darren Huckerby, who did well for him, but it was difficult for them to make the kind of movement that Robbie did.
"Gordon asked Robbie 'who taught you that kind of movement?' and Robbie told him it was all done playing in the streets. He was laying the ball off and spinning and that kind of stuff.
"It was all stuff he did as a boy playing street football. It is a measure of how much he has made himself a very good footballer.
"You can see in training that he loves it and wants to be involved all the time."
