The couple wed in Montecito, California on Saturday, a source close to Pratt tells CNN.
Pratt, 39, and Schwarzenegger, 29, announced their engagement in January after dating quietly for months.
“Sweet Katherine, so happy you said yes!” the “Guardians of the Galaxy” actor wrote. “I’m thrilled to be marrying you. Proud to live boldly in faith with you. Here we go!”
Schwarzenegger is the daughter of Arnold Schwarzenegger, the actor and former California governor, and broadcast journalist Maria Shriver, a niece of President John F. Kennedy. Pratt is also known for his roles in “Parks and Recreation” and “Jurassic World.”
Pratt has a son, Jack, with his ex-wife, actress Anna Faris. They separated in 2017 after eight years of marriage.
Faris offered words of encouragement on Pratt’s Instagram post announcing his engagement to Schwarzenegger: “I’m so happy for you both!”
CNN has reached out to Pratt’s representative for comment.