The stars tied the knot this weekend, a source tells PEOPLE. Reps have not yet responded to requests for comment.
According to another source, the wedding took place at The Secret Garden at Parrish Ranch in Oak Glen, California, a secluded spot surrounded by apple orchards, ponds and mountain views.
Kutcher, 37, and Kunis, 31, met while playing love interests on the Fox sitcom, which ran from 1998 to 2006.
"My first real kiss ever was with him on the show," she said in W magazine's August issue, adding, "We all get movie star crushes. I'm marrying mine."
But their romance didn't really blossom until years later: The stars began dating in 2012, got engaged in February 2014 and welcomed daughter Wyatt Isabelle in October.
"It's unbelievable," the Two and a Half Men actor told Conan O'Brien in October of becoming a dad. "It's the greatest thing on Earth."
The couple spent months keeping fans guessing about whether they were married or not.
Kunis replied "Maybe" when Late Late Show host James Corden asked her if they had tied the knot in March, and Kutcher stirred the rumor pot by posting a Facebook message reading "Happy New Year" from "The Kutchers."
This is Kunis' first marriage and Kutcher's second (his divorce from Demi Moore was finalized in November 2013).