UCLA police said the first of two incidents occurred about 3 p.m. April 3, when a female student said she noticed a man peering at her over a neighboring shower stall door in Sproul Hall.
Just hours later, police said, there was a similar report from a second woman. They said the woman reported seeing a man holding a cellphone over the door about 5 p.m.
"It's scary because you don't know what they're going to do with that photo," Sproul Hall resident Christina Daniel told KTLA.
The first incident wasn't reported until later that evening, the second one not until the following week, police said.
The man was described as being about 35 to 40 years old and 5-foot-8 with a stocky build. According to police, he has short blond hair, blue eyes and wrinkles on his forehead, and was seen wearing a dark gray sweater and pants.
Police are urging students to be aware of their surroundings and to report suspicious activity. Anyone with information was asked to call UCLA police at (310) 825-1491.