Nowadays, surgeons have to deal with more and more complicated interventions. Model of human soft tissues can help surgeons by providing further information on the deformation of specific organ. The model developed in the Computer Assisted Medical Intervention laboratory in Grenoble is modelling deformations of organs and interaction with needles. In order to improve the processing time of this model, the Graphic Processing Unit (GPU) has been used for its capacity to to parallel computation. These processors have already been used to compute mathematical operations. Today, GPU is not only used to display images but also to improve computation time.Programming GPUs needs other methods than usual CPU algorithm and other tools like texture considered as an array in the graphic card. This project describes the different step to use these specialized processors. Models’ deformation from four to more than two hundred particles have been tested in order to study the efficiency of the graphic card.