Surveillance cameras captured video of the violent attack which occurred around 7 p.m. Tuesday.
Police say the suspect entered the business, grabbed the female employee, dragged her to the rear of the location and attempted to sexually assault her. He eventually left the area, police said.
Authorities did not specify which store the assault occurred at.
The suspect was described as a 30-year-old Hispanic man with black hair, standing around 6 feet tall and weighing about 180 pounds. He was last seen wearing a green jacket and blue pants.
The investigation is ongoing. Anyone with information regarding this incident is urged to contact Van Nuys Officer A. Vardanian of the Sexual Assault Detail at (818) 374-0008.