The accident occurred when a cargo train rammed into the back of a passenger train near the city of Bhairab, about 80km (50 miles) from the capital Dhaka.
Two passenger carriages derailed and overturned, trapping and crushing many people inside, according to Sadiqur Rahman, a local government administrator.
Rescuers were seen cutting through the wreckage to reach the survivors, as hundreds of people gathered around the site.
More than 50 injured people were taken to different hospitals, said Rasel Sheikh, the local police chief.
He added that the death toll could rise as some of the wounded were in critical condition.
The cause of the collision was not immediately clear, and an investigation was underway.
Railway services in the region were suspended following the incident, officials said. (ILKHA)