Guests included Scarlett's mother, Melanie Sloan, and her brother, Adrian Johansson, Us Weekly reported.
The stars began dating in February 2007, shortly after Reynolds ended his relationship with singer, and fellow Canadian, Alanis Morissette.
Johansson most recently starred in Woody Allen's "Vicky Cristina Barcelona."
In addition to the sophomoric sex comedy "Van Wilder," Reynolds starred on the TV show "Two Guys, a Girl and a Pizza Place" and took a romantic turn in "Definitely, Maybe.
It's the first marriage for both stars.