Twilight star Facinelli and 90210's Garth, who wed in 2001, made a joint statement assuring fans of their family commitment.
"While we have decided to end our marriage, we both share the same deep love and devotion to our children," the pair told Us Weekly.
"We remain dedicated to raising our beautiful daughters together. We ask for privacy and respect during this time."
Facinelli and Garth, whose romance blossomed shortly after meeting on the set of 1996 film An Unfinished Affair, are parents to Luca, 14, Lola, 9, and Fiona, 5.
Garth, unlike Facinelli, was previously married. The 39-year-old got hitched to musician Daniel Clark in 1994, before splitting two years later.
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