Hip replacement, also known as hip arthroplasty, is a surgical procedure in which hip joint is replaced by an artificial implant. It application is associated to different kind of diseases such as bone arthritis, rheumatoid arthritis and hip fractures. Modeling of biomechanical systems using the Finite Element Method (FEM) becomes in a powerful tool for orthopedics specialist in order to predict the prosthesis behavior under different circumstances. Also those models can contribute to evaluate the influence of different parameters in the successfully prosthesis lifetime as a computational predictive technique before a surgical intervention. Two Bi-dimensional models were presented for two different situations; with and without prosthesis attached to the femoral bone. Also, those models were compared, and the model with the prosthesis inserted shows interesting results in a zone of the stem, which correspond to one of the common stem fractures among other interesting results discussed.