Another member of the family, Khokon Boshak, 42, was rushed to Chittagong Medical College Hospital in a critical condition.
The fire broke out and engulfed the house of Abdul Malek in Mohajonpara area of Parua union in Rangunia upazila at around 2:00 am.
Abdul Hamid Mia, deputy assistant director of Chattogram fire service, said firefighters reached the spot after getting the information and they could tame the flames around 4:00 am.
An accidental fire outbreak was suspected to be the reason of the deaths.
However, Hamid said the exact reasons for the fire and the extent of damage could not immediately be confirmed.
Abu Bakar, sub-inspector of Rangunia police station, said: “The bodies of five members of the family were brought to the police station in the morning.”