Introduction: It is known that sexual assault victim's contacting to water may decrease the detectability of sperm cells on the body of a victim. The features of water (i.e. chemical and biological) also have an importance in this respect. In this study, it is aimed at studying different kinds of water in terms of the detection of sperm cells in vitro. The difference of the study from other studies in the literature is the usage of different types of water and the search for detectability of sperm in these water samples regarding both time and dilution factor.