The Red Devils boss was in determined mood when discussing the future of the club's 18-year-old prodigy following reports that he may move elsewhere when his contract expires
The 18-year-old’s future at Old Trafford is in question after it was revealed that his contract expires at the end of this season - though United has ramped up its efforts to keep the teenager at the club.
Yet Moyes believes the Belgian-born attacker would be best served by staying at United and placed his talent alongside the likes of Wayne Rooney.
Asked whether he felt Januzaj would leave the club Moyes said: "You're 18, you’re playing for Manchester United — I don’t know where else you would really want to play."
Januzaj highlighted his promise with a double against Sunderland to haul the Red Devils to victory after they fell a goal behind at the Stadium of Light, leading Moyes to compare him to the likes of Rooney.
"Wayne Rooney, Charlie Nicholas, Paul McStay — Adnan would be in that category," Moyes added, before pointing to the importance of giving youth a chance.
"I would have played him three or four weeks earlier, but I didn't feel at the time the circumstances were right to put him in the team," he continued.
"But I think part of this job is to introduce young players. When you're in the dressing room area, you see Sir Matt Busby’s comments on the wall: 'If they’re good enough they’re old enough'. It has been the philosophy of this club.
"The last manager put young players in when he had them, and if I've got more young ones I want to play then I will try to bring them on because I think it’s what they do well here.
"It’s important to remember he's still only 18. Some players will play for clubs when they are 18, but I think to play for Manchester United at that age is a big thing.
"Time will tell what his best position will be. He could arguably be a centre forward, he’s that good with his back to goal. He's also very good coming off the left and off the right, maybe in the No 10 role when he grows with experience.
"He's got no real ego to him. He's a really humble boy and he's been really well looked after by his dad and his family. That's kept him the right way. I think he can handle anything that comes his way.
"I've had words with him since Sunderland and spoken to him about what he has to do. With young boys there are going to be dips at times and there will be games when you see it. We will try to make sure we look for that."