The paper shows a modification procedure of a city bus into a touristic panoramic bus. The goal of this modification is to enable easier tourists sight-seeing while driving on the bus. This intervention requires significant modifications on the vehicle’s body structure, removing solid roof and its carrier, and making two security frames (rollbars) with the aim of protecting passengers in the event of bus rollover. Requirement for placing the modificated bus in the public transport and at the same time the project request, is that the security frames (rollbars) and modified body structure must be strong enough so that in case of rollover bus is leaned over security frames. These frames and the modified body structure must be able to endure the static load, which corresponds to the maximum technical permissible mass of the vehicle. By using the method of finite elements a strength analysis (calculation) was made for the requested load case applied to the proposed construction solution of security frames (rollbars) and modified body structure. This analysis showed that the stresses in such construction would not exceed the Yield strength of materials and that the security frames or body structure will not fracture. By checking the stability (buckling load) of security frame, it was established that there would be no loss of structure stability.