Weinstein, 65, and fashion designer, 41, have two children: India Pearl, 7, and Dashiell Max Robert, 4.
"My heart breaks for all the women who have suffered tremendous pain because of these unforgivable actions," Chapman said in a statement to People magazine Tuesday.
"I have chosen to leave my husband. Caring for my young children is my first priority and I ask the media for privacy at this time."
Us Weekly said the split was announced less than a week after The New York Times published a scathing report claiming Weinstein sexually harassed and assaulted numerous women -- including actresses Ashley Judd and Rose McGowan -- over the last three decades.
He was fired from The Weinstein Co., which he co-founded with his brother Bob, during the weekend.
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