The clerk wasn't injured.
Two men wearing black ski masks, gloves and clothes burst into the Convenient Food Mart at about 11:30 p.m. in the 1900 block of E. Perkins Ave.
One man brandished a knife while the other aimed a mace can at the clerk's face. Both demanded money from the till.
The clerk opened the register and the men grabbed an undisclosed amount of money.
The suspects then ordered the clerk to put her face on the floor, Perkins police Chief Ken Klamar said.
After she bent down, one suspect tried to spray the woman in the face with mace. They both took off.
Police showed up soon after and scoured the area but came up empty.
The clerk described the robbers as being about 5-feet-9 inches with skinny builds.
Klamar said officers got surveillance video from the store Friday.
"The detectives are working as hard as they can to try and solve this," Perkins police Chief Ken Klamar said.
Klamar refused to release a report on the incident citing it was an "ongoing investigation."
The robbery wasn't listed on a call log sheet printed Friday morning.
Anyone with information on the robbery can call Perkins police at 419-627-0824.