The 64-year-old actor started dating his wife about seven years before their 2002 wedding. They have a 13-year-old son, Homer, born in 2000.
"They'll do everything possible to keep things amicable and put their child first," a People source said of the split.
Though there was no specific reason given for the separation, one source told Page Six that the couple had “been spending time apart for quite some time.”
Another source blamed the breakup on lifestyle differences.
They have a place in Bedford [NY], and he likes it because it’s quiet and he likes the solitude. She likes being in North Haven in the limelight. They live next door to Jimmy Buffett and his family, and they’re good friends.
Gere was previously married to model Cindy Crawford, while Lowell has two ex-husbands -- including actor-director Griffin Dunne.