The pair tied the knot outdoors at the Beverly Hills Hotel, in an evening ceremony on the iconic hotel's crystal lawn attended by their son Nick, 22, and daughter Sophie, 19. Shannon donned an ivory Priscilla of Boston gown for the occasion and carried a bouquet of garden roses, also in ivory.
The couple, who've been together for 28 years, wrote their own vows, and for their first dance, were to be serenaded by daughter and maid of honor Sophie singing the Etta James classic, At Last.
In attendance for the event included Hugh Hefner, Bill Maher and Gene's KISS bandmates.
Gene told ET's Mark Steines of the decision to finally propose, "It is time for me to grow up. I'm 62. I've been doing a lot of wacky stuff for an awfully long time…and there's nobody I've ever said I love you to. I even find it difficult to say 'I love you' to my mother. But I love Shannon with all my heart and all my soul, and always will."