The accident at Kathajodi passenger halt in Cuttack claimed two lives and injured around 25 passengers on Thursday.
ECoR said in a statement it had suspended a guard, driver, assistant driver and loco-inspector for negligence.
Railway Minister Suresh Prabhu on Thursady ordered a thorough probe into the accident.
"Ordered immediate probe into the accident of Bhubaneshwar-Badrak train, negligence will be punished severely," the minister tweeted.
According to officials, Bhubaneswar-Bhadrak DMU train collided with a stationary freight train from the rear around 6.30 pm.
The injured persons were admitted to Shrirama Chandra Bhanj medical college and hospital in Cuttack.
