Trachyspermum ammi (Linn.) Sprague fruits have traditionally been used in India as medicinal plant for the treatment of various diseases in both humans and animals such as spermicidal activity. Trachyspermum ammi is a small plant belongs to the family of umbelliferae rich in volatile oil (thymol). In the present study ethanolic extract of Trachyspermum ammi fruits are tested on male reproductive system. Animals are pretreated with ethanolic extract of Trachyspermum ammi at four different doses such as 100mg/kg, 200mg/kg and 400mg/kg for a period of 60 days with the recovery group animals for 120 days at the dose of 400mg/kg. Parameters such as testes weight, sperm count, sperm motility, sperm morphology and histopathological examination of the testis are carried out. The study revealed that the drug posses significant male anti-fertility effect dose dependently. The recovery group reverts back the elevated parameters by increasing the decreased testis weight, sperm count, sperm motility, decrease in production of abnormal sperms and restoring the cellular pattern of the testis. These findings indicate that Trachyspermum ammi fruit extract is a very good choice of male anti-fertility activity drug which can be formulated as a male contraceptive formulation.