Railway Minister Mujibul Hoque flagged off two such trains at the Chittagong Railway Station at noon.
One of them, called the Chittagong Circular Train, will daily ply in the port city, having a minimum fare of Tk 15.
The other, Chittagong-Laksham Commuter Train, will daily run between Chittagong city and Laksham, in Comilla district. The maximum fare on the 120-km route is Tk 60.
Each DEMU can carry 300 passengers at a time.
Environment Minister Hasan Mahmud and Primary and Mass Education Minister Afsarul Islam were also present at the function.
The government had signed an agreement with a Chinese company in August 11 to procure 20 commuter trains at a cost of US$ 58.31 million. So far, 14 DEMUs have been imported from China.
Earlier on April 24, Bangladesh Railway made headway in its expansion programme by introducing a modern and speedy DEMU train service on the Dhaka-Narayanganj route.
DEMUs can attain speed up to 80 kmph as they have engines at both ends.
If the present services prove successful, more such trains are expected to be introduced in other parts of the country.