The centrifugation on discontinued Percoll gradient is a technique of sperm preparation, which has enabled better success of in-vitro fertilization. In this work, we have analysed the movements of spermatozoa separated in different Percoll fractions after 4 hours of incubation at 37°C and under 5% of CO2. These measures are made by computer assisted videomicrography (Cell Soft). From this study, we notice that the more the Percoll concentration increases, the greater is the curvilinear velocity, the linearity and the lateral amplitude of the head. The 100% and 90% Percoll fractions help to get spermatozoa with good movement features, indicating the use of this technique in medically assisted procreation.