A couple and two of their children died on spot when the motorcycle they were riding on collided with the bus in Nankana Sahib district, Dawn reported.
The other four victims who died in the accident were passengers on-board the bus.
The bus was going from Lahore to Jaranwala in Faisalabad district, when it collided with the motorcycle.
Police and rescue teams have shifted the bodies to the nearby hospital.
Pakistan has one of the world's worst records for fatal traffic accidents, blamed on poor roads, badly maintained vehicles and reckless driving.