The incident happened on Sunday, June 23, around 10:30 p.m.
Police said a 24-year-old woman was walking westbound on Roscoe Boulevard from Owensmouth Avenue when the man attempted to sexually assault her.
In surveillance footage released by police Friday, it appears the suspect was following the woman for a few minutes.
Police also released a sketch of the suspect. He's reportedly between 25 and 30 years old with black hair and brown eyes.
He's about 6 ft. tall and weighs 200 pounds. He was last seen wearing a red shirt, an orange and blue long-sleeved flannel and dark blue pants.
Anyone with information is urged to contact police.