Many are still missing. Deputy commissioner, Johar Ali, and senior police officials are supervising the rescue task.
The Barguna-bound launch MV-10 from Dhaka had more than 1000 passengers.
Unharmed passengers said the launch caught fire while it was on the Sugandha river in Jhalokati. The launch was later diverted to the bank near Diakul village.
Kamal Hossain Bhuiyan, deputy director of Barisal Fire Service, told Prothom Alo that a total of five units were working to rescue the victims.
Rescue operations are being hampered due to heavy fog, the fire service official said.
Kamal Hossain Bhuiyan said that it was initially suspected that the fire originated from the engine room of the launch.