The 20-year-old signed a five-year contract with the Blues on Friday following weeks over speculation linking him with a transfer to Stamford Bridge.
And the Netherlands international, who made 33 Eredivisie appearances last season and scored eight goals as Vitesse finished fourth, revealed that he has spoken to Mourinho since securing his move to west London.
“I spoke with the manager and he had some good words for me,” Van Ginkel told Chelsea’s website.
“If a trainer like this says these things to you it makes you really proud and I am happy to work with him.”
Van Ginkel will begin pre-season training with his new team-mates on Monday and the midfielder says he is raring to go.
“I look forward to it a lot,” he continued. “It’s not scary, but I will be a little bit nervous maybe.
“Playing with players like Frank Lampard and John Terry will be a huge thing. I played three years at Vitesse, but the Premier League is very good, and I will enjoy playing with these players with this experience.”
He added: “I’m very happy to be here at such a nice club with great players. I am really happy, the stadium is good and the training ground is fantastic.
“I know about all the players and will meet them on Monday. I expect a lot, I’ve watched matches and it’s really nice to be here.”
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