Abstract: Extremely Low Frequency Electromagnetic Fields (ELFEMFs) are produced by a variety of different sources. The aim of this study was to evaluate the influence of ELFEMF on function and structure of testis in rats. Experimental adult male Wistar rats were exposed to a 50 Hz ELFEMF, 1 MT (emitted from solenoid) for 24 h daily during 135 days. The sham rats were subjected to sham exposure and the control rats were kept in animal room. In final, blood samples collected for the determination of the testosterone, LH and FSH concentration in the plasma. The testis was examined using light microscopy. Results showed that in EMF exposed group plasma concentration of testosterone was decreased (p<0.001), plasma LH concentration was increased (p<0.01) and FSH showed no significant changes which were accompanied by marked atrophy of seminiferous tubules and marked increase in interstitial connective tissue as well as Leydig cell hyperplasia. In conclusion, long term exposure to ELFEMF could have adverse effects on mammalian reproduction.