The 22-year-old Dane made 37 appearances for Villarreal last season after becoming the club’s first-choice goalkeeper.
“This move is a dream come true,” said Jorgensen. “I am very excited to have signed for Chelsea, one of the biggest clubs in the world.
“I can’t wait to get to know everyone and to start playing with all my new team-mates.”
Jorgensen is expected to compete for Chelsea’s number-one position with Robert Sanchez.
Born in Sweden, Jorgensen represented the country at age grade level before switching allegiance to Denmark Under-21s, who he qualifies for through his paternal heritage.
He signed for Villarreal as a 15-year-old and progressed through the club’s youth set-up before making his senior debut in October 2020 for the B side.
Jorgensen, who made his La Liga debut in January 2023, has flown to the United States to join Chelsea’s pre-season tour.
The Blues have three games left so he could feature against any of Club America, Manchester City or Real Madrid before they travel home next week.
Chelsea begin their Premier League campaign at home to champions City on Sunday, 18 August.