Fifteen others were injured when the building, located in the al-Maamoura district, collapsed Wednesday, Ahram Online reported.
Police said they arrested the building's two owners and were investigating the collapse.
Ahram Online said residents had warned authorities about a possible danger after sewage water flooded the area after days of heavy rain.
The moisture caused cracks to form on the building.
Housing Minister Tarek Wafiq said the government should be held responsible for the collapse, but said the building was unlicensed.