Introduction: Lamotrigine is one of the never anti-epileptic drug. In this study the effects of lamotrigine have been observed on serum concentration of LH (Luteinizing hormone), FSH (Follicle-stimulating hormone), testosterone ,body and testis weight in male rat.

Methods: The animal used in this experiment were 40 adult male rat from wistar race which were divided in to 5 group of 8.consisting of control group which received nothings, Sham group which received 0.2 ml distilled water via oral. Experimental group which received 100, 200, 400 mg/kg lamotrigine via oral after 14^th day body weight were measured in all group and then the blood sample was taken from heart and concentration of LH.FSH, testosterone was measured. In addition the testis were separated and testis weight were measured in all group.

Results: The result show that concentration of LH in experimental group did not show significant difference in compared with control group but in experimental group received 400mg/kg of lamotrigine  show a significant decrease in concentration of FSH and testosterone in comparison with control group .In addition lamotrigine had effect and testis weight in middle and high dose was reduce.

Conclusion: Lamotrigine, an antiepileptic drug, reduced reproductive activity by inhibiting of hypothalamic-pituitary-gonadal axis in adult male rats.