PURPOSE: The aim of the present study was to demonstrate the expression of inflammatory marker -IL-4 in visceral adipose tissue, testis, and blood serum when experimentally presented for obesity in rats. METHODS: We used a high-lipid diet model leading to the development of obesity in rats. 50 male Wistar rats were used. They were divided into two groups - control group (C) - fed with standard rodent food - experimental group (E) - fed high lipid diet for a period of 4 weeks. Blood, visceral adipose tissue and testis were collected after the end of the experimental period. For the determination of IL-4 in the testis and visceral adipose tissue, we used the immunohistochemical method and in the blood serum the ELISA method. RESULTS: We detected that IL-4 is increased in the control group blood serum, adipose tissue, testis (the seminiferous tubules and the interstitial cells) of the control group compared to the experimental group. CONCLUSION: Тhe study shows that obesity leads to the generation of complex and multilayered interactions between adipocytes, IL-4 and germ cells with adverse effects on the germinal epithelium of the testicle.