The 20-year-old England international was signed by United in January before being immediately loaned back to Palace, who went on to win the Championship play-off final.
It has been suggested Palace might ask United for another loan deal for winger Zaha as they bid to survive in the Premier League - but Holloway has no such plans.
"I don't think for one minute I'd even consider asking David Moyes about signing him right now," Holloway told talkSPORT. "I don't think it's fair to the boy. He's got to have a go at United.
"I'm sure I know Moyes that well that if there was a club in the Premier League that Wilfried Zaha wanted to play for, if it wasn't Manchester United, I'm sure it would be us. So, I'm sure the phone would ring.
"Let's be perfectly honest, I think the boy is so exciting he's going to have a chance at United and I can see him getting in their first team. I genuinely mean that.
"I wish him all the best in his Manchester United career and well done to them for buying him.
"Sir Alex Ferguson very rarely gets them wrong and David Moyes will be delighted he's found that talent in his midst, because he can win games at the very, very top level."