The bodies recovered so far included women and children, said Jahurul Islam, district administrator of northern Panchagarh, where the accident occurred.
"The rescue operation for those missing is ongoing," he said.
Islam said he did not know the exact number of people missing, but passengers said more than 70 people had been on board.
Hundreds of people die each year in ferry accidents in Bangladesh, a low-lying country that has extensive inland waterways but lax safety standards.
At least 26 died in May after an overcrowded speedboat collided with a sand-laden bulk carrier and sank on the Padma River.
(Reporting by Ruma Paul; editing by David Evans)