The aim of the study was to find out if pheromone was one of the responsible factors leading to rape. Search in literature revealed many interesting facts. Majority of rape took place on the day or nearer to ovulation. Many rape victims became pregnant. In normal life, among couples most of the sexual intercourse happened on this day, more than on other days. Smell of the women on this day was different and was more attractive to men. Vaginal smell also differed on this day. One study showed many men were able to recognize a woman’s urine of ovulation day by its smell. It was not similar on other days. All above lead us to conclude that women exuded a sex attractant or pheromone on the day of ovulation which attracted men. Probably this is the hidden biological cause ending in rape.