The aim of this study was to evaluate the efficacy of Blutstan staining of human spermatozoa for predicting the spermatozoa capacity of fertilization in human IVF. Blutstan, a prestained glass slide coated with dyes, is able to identify activated sperm quickly and easily. Acrosomal reactivity of spermatozoa was evaluated with this slide glass at the insemination of IVF of 30 couples. There was significant correlation between the Blutstan reactivity and the fertilization rate (r = .52, p < .01). Furthermore, spermatozoa with high Blutstan reactivity were fertilized oocytes polyspermy. This method was rapid, simple, and useful for detecting activated sperm and predicting for the polyspermic fertilization in clinical setting.