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To understand the effect of attitude angle on helicopter water ditching ,a finite element model (FEM ) of helicopter water ditching was established via the nonlinear finite element method .Based on the LS-DYNA soft-ware ,the finite element model of the helicopter was established .Different attitude of helicopter water ditching was simulated and analysed .Three pressure measuring points were arranged in the aircraft belly area .The pressure curves were provided seperately .Finally ,the effects of attitude on helicopter water ditching was discussed ,partic-ularly the stability and the overload of helicopter .Through the contours of stress ,it can be figured out that the maximum pressure locates at the position of aircraft belly where stiffness is larger .Then simulation and experi-mental results were compared .The difference of peak acceleration along the Z direction was small .Therefore ,this method is feasible and helpful for the design of helicopter water ditching .