The mishap occurred this morning when the state roadways bus, which was coming from Visakhapatnam to Rajahmundry, hit the oil tanker from behind, they said.
The injured were rushed to the nearby government hospital for treatment, police said, adding that the condition of the driver of the bus was stated to be serious.
A case has been registered in this connection while the further probes are on, they added.
Recently, a private bus fell off a bridge in Maharashtra, claiming more than 25 lives while three bus met the same fate in Andhra Pradesh yesterday in which one person died and more than 20 people injured.