The human activity of walk and run leads to the join femur-hip a cyclic load and a fluctuant stress and strain that is able to produce cracks or fracture due to fatigue that is a progressive and permanent change in material endurance. Brazilian standards define the position, intensity and number of cycles of the load to simulate the real life of a new protheses designed. The aim of this study is to predict the failure progression of ASTM F75 alloy femoral prostheses under fatigue analysis whit finite element method for simulation. The alloy F75 shows satisfactory results in static analysis, but in the dynamic analysis nether exceeds 5 million cycles and it presents fail in the safety factor to fatigue.