Background and Aims: High prevalence of infertility and many related problems has become a big problem for economy and healthy. This study is to determine the effect of dietary omega-3 based on hypothalamic–pituitary–gonadal axis (HPG) activity and testosterone plasma level in adult male adult wistar rat.

Methods: This experimental study was conducted on 40 adult male wistar rats. Animals were with an average weight of 150±20 gr. They divided into five groups (n=8), including the control group, saline group and experimental group of minimum , average and maximum in which consumed dietary including omega-3, 0.25 and 0.5 and 0.75 mg/kg dose the 29 days. The blood was take from the heart of animals. Using Radioimmunoassay methods, testosterone and LH levels were measured. In this study effects of dietary omega-3 on testosterone secretion level in experimental groups, was compared with saline and control groups.

Results: The results of a compared LH and testosterone level with the control group (0.167±0.02 and 0.182±0.02) and all experimental groups, particularly at the maximum dose (0.654±0.09and 0.584±0.12 respectively), showed a significant increase.

Conclusion: It was shown that the increase in omega-3 plasma levels of in the experimental group led significantly increase in the testosterone and LH level. This study showed that consumption of Omega-3 oils, significantly increase plasma levels of testosterone and LH hormone.