Ten fire units were needed to battle the flames at the five-story building in Cairo's Bab al-Shareya district, al-Masry al-Youm reported.
The fire was put out about three hours after it started.
Six employees at the shoe workshop were sleeping when the fire started and all of them perished, authorities said.
Shamshoun Youssef, head of the Civil Defense Chamber of Operations, the government agency responsible for firefighting services, said firefighters had a difficult time putting out the fire because the street the building was located on was very narrow.
An initial investigation indicated the fire may have been started by an electrical short circuit in the shop.