The incident took place at around 7am near Sonamuri Tek on Dhaka-Sylhet highway, said police.
The dead and injured, all passengers of the microbus, are yet to be identified, police added.
The injured have been admitted to Narsingdi District Hospital, said Shibpur Model police station chief Abul Kalam Azad.
A Sylhet-bound bus from Dhaka operated by Mitali Paribahan collided with a microbus packed with wedding guests on its way to Chandpur from Raipura in Narsingdi.
Four of the passengers, including a child, died on the spot.