Van Persie's move from Arsenal to United in August broke the hearts of many fans of the London club.
The match at Old Trafford will be the first time the Dutchman has come up against his former team-mates.
"I hope a respectful (reception) because he played for us for eight years," Wenger said. "He's done well, very well for us, and you want him to be respected.
"You campaign against discrimination; it was still the case last week so why should it not be the case this week?"
Van Persie scored 132 goals during his time at the Emirates, with 37 of those coming during his final season, helping Arsenal to third place in the English Premier League after a disastrous start to the campaign.
While Olivier Giroud is yet to find his feet and Marouane Chamakh remains the forgotten man despite his Capital One Cup exploits, Wenger said he has not considered what difference van Persie would make had he stayed.
"That's a question that is very difficult to answer because at the moment I am focused on doing well with the players I have," he said.
"To start to think how much we will miss him will not help us to do well."
Van Persie started his career in Manchester with a bang, scoring 11 goals in 15 games, though Wenger is not surprised.
"He is certainly the most efficient striker, and Robin is very intelligent around the box," he added.
"His technique is absolutely amazing, so with his intelligent runs he will take advantage of that."