The woman had last been seen on Friday in Sheerness, and was then found in Victoria Street, Gillingham, on Monday morning, Kent Police said.
A 42-year-old man, a 30-year-old man and a 17-year-old boy, all from Gillingham, have been arrested on suspicion of false imprisonment.
The two men have also been arrested on suspicion of rape.
They remain in police custody.
Two men and a boy have been arrested after a woman was reported missing over the weekend.