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Buses are widely used mode of transport in worldwide. With growth in economy, the numbers of buses have increased tremendously both in rural and urban areas. With increased number of buses, the issue of safety of passengers and the crew assumes special importance. A large number of bus accidents involve rollovers and falling into ditches or downhill sides. Bus rollover is one of the most serious types of accident as compared to other modes of bus accidents. In the past years, it was observed after the accidents that the deforming body structure seriously threatens the lives of the passengers and thus, the rollover strength has become an important issue for bus and coach manufacturers. In the European countries, the certification of sufficient deformation strength when overturning is compulsory for the approval of a coach according to the ECE 66-02 regulation. According to the said regulation, the certification can be gained either by full-scale vehicle testing, or by calculation techniques based on advanced numerical methods (i.e. non-linear explicit dynamic finite element analysis). The quantity of interest at the end is the bending deformation enabling engineers to investigate whether there is any intrusion in the passenger survival space (residual space) along the entire vehicle. The simulation specifies either overturning of the vehicle structure from tilting platform or the impact of a plate on the coach structure as it would correspond to the crash of the structure when falling onto the ground. According to the ECE 66-02 regulation, a passenger's survival space is defined in the coach model to check whether there is any intrusion into the survival space during the rollover. This ensures that the coach structure has sufficient strength to avoid intrusions into the survival space. The effect of passenger and luggage weights on energy absorbed by the coach structure during rollover will be also discussed. Rollover test on a complete vehicle is the basic testing method, the expensive cost and time-consuming nature make it difficult to be implemented during the process of product research and development (R&D). The high cost of real tests and difficulties in collecting data has resulted in an increasing interest in the analytical and computational methods of evaluation. The advancement of computer simulation technology enables the quick assessment of coach rollover crashworthiness even at the initial design phase. Simulation-based rollover analysis can assist, even replace the experimental testing, if properly performed. With the advancement in computer simulations, full finite element validated vehicle models are being analyzed crashworthiness characteristic and occupant safety of vehicle. In this thesis, the rollover analysis of the coach structure will be performed nonlinear explicit dynamic FEM code RADIOSS software as a solver because of the time integration, large displacements, local bucklings and plastic deformations. FE model of the rollover analysis will be generated with HyperMesh and HyperCrash pre-processor softwares. The results of the explicit dynamic rollover analysis results and the strength of the vehicle will be assessed with respect to the requirements of the official regulation with using HyperView post-processor software.