Mourinho, sacked by the Blues in December, was confirmed as Louis van Gaal’s successor at Old Trafford on Friday.
Hazard won the Premier League title under the self-styled Special One at Stamford Bridge, and he is already looking forward to a reunion with his old boss.
“Mourinho is a fantastic manager,” Hazard said. “I wish him good luck for the next season.
“I can’t wait and just want to play against Manchester United. He’s a good manager with a lot of experience. He’s at a big club now and he will just want to win games.”
Hazard endured a disappointing season for Chelsea as the club failed to mount a title defence and missed out on European qualification.
He didn’t score his first goals in the Premier League until April and was below-par for much of the campaign – although he did show glimpses of his old form towards the tail-end.
There has been talk the 25-year-old could move on in the summer – but Hazard insists, like fellow Belgian Thibaut Courtois, he fully expects to remain at Chelsea after talks with incoming boss Antonio Conte.
Speaking to Sky Sports, he said: “I’m happy. I’m always happy. I have spoken to [new boss] Antonio Conte.
“For now, I’m 100 percent sure I’ll compete at the Euros. After, I will think of Chelsea.
“But I want to finish well at the club. So like Thibaut (Courtois), I will be at Chelsea 99 per cent next season.”