The superstar Swede joined the Red Devils on a free transfer over the summer after leaving Paris St-Germain.
He looks to be the perfect foil for rising ace Rashford, who burst onto the scene in the second half of last term with a barrage of goals.
And Mourinho thinks Ibrahimovic will be invaluable for the home-grown talent as he looks to continue learning and developing his game.
Mourinho told BT Sport: "He [Ibrahimovic] is brilliant with the young boys. I think, for Rashford, this is a gift.
"People can say he is not going to play every game from the start, like in the second part of last season, but this is a gift for the kid, too.
"We are so happy to have him. We couldn't find a better striker than him to give us the stability we need."
The pair are likely to feature together on a regular basis as Mourinho goes in search of silverware at Old Trafford.
