The Red Devils completed a swoop to sign Dalot in a deal thought to be worth around £17m for the versatile defender from Portuguese side FC Porto.
Dalot, who has signed a long-term deal with the Old Trafford outfit, is capable of playing at both right-back and left-back next term.
The 19-year-old is the first Portuguese player to move to Manchester United under his compatriot Mourinho following the manager’s appointment in 2016.
Dalot has a promising reputation after the full-back broke into the FC Porto team last term to rack up eight appearances in all competitions.
The Portugal Under-21 international was part of the FC Porto team that lost 5-0 to Premier League side Liverpool FC in the Champions League round of 16.
Dalot is excited about the prospect of working under Mourinho following his transfer to Manchester United.
“Yeah, it’s very good,” Dalot told Man United’s website. “It was very important to make this choice and I hope to help him, because I know that he will help me to improve a lot.”
He added: “Yeah, I think that age is not very important now in football. I think that if you work and you improve, I think you can handle it.”
Manchester United finished in second place in the Premier League table after the Red Devils finished above Tottenham Hotspur and Liverpool FC.
The 20-time English champions lost 1-0 to Chelsea FC in the FA Cup final after Eden Hazard scored the winner from the penalty spot in the first half.
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