Two men carrying guns held up the adult video and book store on West El Camino Real shortly before 11:20 p.m. on July 2, police said.
The men came into the store wielding semi-automatic handguns and demanded that the cashier fork over the money in the register, said Jaime Garrett, spokeswoman for the Mountain View Police Department.
The cashier complied, and the men fled out of the back door of VCO Adult Videos, located at 1063 W. El Camino Real, Garrett said. The men had their faces obscured by some kind of mask. They wore black sweatshirts, dark pants and dark shoes.
The robbers also took a cell phone. The amount of money stolen was not disclosed.
The store has security footage which detectives are currently reviewing, Garrett said.
The same store was robbed in December by a man who said he had a gun in his pocket.