The Ottawa County Sheriff's Department identified the body as 55-year-old Barbara Westveer, who disappeared a week ago.
An autopsy showed there were no traumatic injuries to the body and a cause of death is undetermined. There were no apparent signs of a struggle or foul play, police said.
Toxicology results are expected next week.
Westveer was reported missing May 28 by her husband after she failed to show up for an appointment. Investigators found her cellphone, purse, keys, medication and car at the couple's home along Lake Macatawa.
Authorities said Westveer and her husband had recently been separated, but they were working toward a reconciliation, and she had struggled with depression in the past.
Westveer's body was discovered Monday floating on the north side of Lake Macatawa by a person operating a personal watercraft.