The accident occurred on a motorway in Hasan Abdal area of Attock district.
The bus was traveling from Lahore to Mardan in Khyber-Pakhtunkhwa province.
The rescue teams shifted the dead and injured to a nearby hospital.
At least 15 people have lost their lives while over 35 others have injured in the incient, the police said.
Special Assistant to the Prime Minister on Overseas Pakistanis and Human Resource Development Sayed Zulfikar Abbas Bukhari expressed grief over the incident and directed the civil administration to provide assistance to the victims.