The pair were reunited at United last year after being former Ajax teammates.
Mazraoui told United Review: "As a defender, he's really aggressive.
"He likes to be in the duels and win his duels. On the ball, he's also really, really good on the ball. You see the Ajax school, of course, in his style of play.
"He makes really good decisions, with the ball and also without the ball, and he's really, really vocal, which is really important for his position. So, you know, it's always easier when you have somebody behind you, like telling you a little bit left, just a little bit right, to block a certain passing line.
"That's how he is on the pitch and, outside the pitch, he is just relaxed, a relaxed guy. Really open and really funny. I think he's a really good guy to be around. Yeah, I just love the guy."
De Ligt, in 2018, became the only player to win the Golden Boy award.
And Mazraoui continued: "I'm really, really proud of the performances he is putting up now. I think he should stay like this and even improve more because I know he can be even better than this.
"He is still quite young, yeah, I think he even won the Golden Boy (award). I said lately for fun, also a little bit serious, that he is reaching his form of a Golden Boy again. I think he is getting into his prime at this point."