The 22-year-old central midfielder completed the formalities of his move today and is to fly out to Singapore to meet-up with his new teammates ahead of next week's Barclays Asia Trophy.
He has become the Club's fourth signing of the summer following the arrivals of Phillip Wollscheid, Jakob Haugaard and Joselu.
van Ginkel, who joined Chelsea from Vitesse Arnhem in 2013 in a deal reported to be worth in the region of £8million, spent last season on loan with Italian giants AC Milan, making 17 Serie A appearances.
A box-to-box player, he scored 18 goals in 93 league appearances for Vitesse - and was also voted Dutch Talent of the Year - which brought him to the attention of Chelsea who held off competition from a number of other clubs to secure his signature.
City Chief Executive Tony Scholes said: "Marco is a player with fantastic potential and we are delighted that he will be spending the 2015/16 season at the Britannia Stadium.
"Marco is keen to make a big impression in the Premier League and believes he can do that with Stoke City."
Manager Mark Hughes said: "Marco is the kind of player we have been looking to bring to the Club. He will bring great energy to the side and is capable of scoring goals from midfield, as he showed during his time with Vitesse.
"I'm looking forward to him linking up with the squad in Singapore and getting the chance to work with him on the training ground and see him in action in the Barclays Asia Trophy."
van Ginkel is an international teammate of City left back Erik Pieters having been capped twice by Holland.