The 45-year old German takes his Latics side to the Etihad Stadium for the FA Cup quarter-final on Sunday and says he will try to keep his emotions in check after playing for City between 1994 and 1998.
"I would be lying if I said no," said Rosler when asked if it would be an emotional visit.
"But I have to make sure that the professional side takes over and not the emotional side.
"That will be my personal focus on the day - to look to enjoy the occasion, but to make sure I'm absolutely concentrated on the job in hand."
Rosler was diagnosed with cancer in 2003 and it was the City fans who helped him recover after the former forward heard them chant his name over the phone while in hospital.
He added: "It will be interesting.
"When I was just recovering from cancer and had finished with my treatment, I went there to say thank you for the support I got from the club and from the supporters, and that was a very emotional moment.
"Now, all these years later, I'm going to be there with a wonderful football club as a manager.
"It is quite a story, and the emotions will be there, but I also know I am a very professional guy and I can focus on the job in hand.
"So we will see - ask me after the game!
"It was very special, the way they helped me to recover. It was a very important moment, I always felt.
"It put a smile back on my face and gave me new hope and new motivation to get through a very difficult time."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball