In her upcoming book, the 30-year-old accuses singer Robin Thicke of groping her without consent during filming of the 2013 video.
Thicke, 44, has not yet responded to the BBC's request for comment.
The allegations, first reported in the Sunday Times newspaper, feature in Ratajkowski's forthcoming book My Body.
The 30-year-old claims Thicke "returned to the set a little drunk to shoot just with me".
"Out of nowhere, I felt the coolness and foreignness of a stranger's hands cupping my bare breasts from behind. I instinctively moved away, looking back at Robin Thicke," she writes.