No charges have been filed and attorney Tim Jansen, who is representing Winston, denied the allegations, the Tallahassee Democrat reported.
The complaint was filed with police Dec. 7, 2012.
Jansen said he spoke to police in February and was told that the case had been closed.
"This case has been going on for over a year. The case was basically closed and we're not sure why it's opened up," Jansen said.
The FSU Athletic Department said it will not comment until police finish their investigation and that Winston's status on the team has not changed.
The police report, obtained by the newspaper, does not mention Winston by name.
The document states that sexual battery took place at an apartment last December.
The suspect is unknown, the report states, but is between 5-foot-9 and 5-foot-11, and 240 pounds.
Winston is 6 foot 4 and 218 pounds.
Evidence was collected from the complainant's body, and photos were taken of the complainant, as well, the report states.