Toronto police say that the alleged incident unfolded on the evening of June 28, 1998, in the Queen Street West and Beaconsfield Avenue area.
Police say a 33-year-old woman who worked in the sex trade was approached by a man.
It is alleged that the man took the woman to the rear of a building, where she was sexually assaulted and robbed.
Police say the suspect rode away on a mountain bike.
The incident was reported to police, but the suspect could not be identified.
A new cold case investigation has led to an arrest.
A 56-year-old Toronto man faces charges of sexual assault, robbery and failing to comply with probation. The accused is due to appear in court on Friday.