The eldest Jonas brother married girlfriend Danielle Deleasa Saturday at Oheka Castle in Long Island, N.Y., according to the magazine.
"We're so happy that we're finally married and we were able to share the special moment with family, friends and loved ones," the couple tells People.
The evening nuptials were attended by 400 guests, including celebrities like Demi Lovato, the magazine reports. Jonas' brothers and band mates Joe and Nick served as best men. Deleasa, 23, walked down the aisle in a strapless Vera Wang gown before exchanging traditional vows with Kevin, 22. The newlyweds' reception included Caribbean, Asian and Italian dishes, among others, according to People.
Jonas and Deleasa met in May 2007 and became engaged this past July.