Electromagnetic field is a stress factor which can interfere with the functions of body organs. This study aims to evaluate the protective impact of the aqua extract of Persian Gulf sea cucumber on damages induced by low frequency electromagnetic field in male gonads of Balb/C mice. Mice were divided into control, sham-exposed and 5 experimental groups. The experimental groups were then exposed to electromagnetic field (for 10 days and 4 hours per day). Experimental groups 2-5 also received extract of sea cucumber (6h before electromagnetic field). The samples were fixed for histological studies and stained by H & E method. The measurement of the diameter and number of seminiferous tubules, testis diameter, testis and epididymis weight, tunica albuginea thickness, the number of spermatogenic cells including spermatogonia, spermatocytes, spermatids, Sertoli cells and Leydig cells was then executed. The results showed that the impact of electromagnetic field exposure was not significant on epididymis weight, seminiferous tubules diameter and tunica albuginea thickness, while its impact on the reduction of the testis diameter and weight, the number of seminiferous tubules and spermatogenic cells was significant in experimental group 1. In addition, the experimental groups pre-treated with sea cucumber extract indicated significant increment, as compared with experimental group 1.The results proved the destructive effect of electromagnetic field on testis tissue parameters, while sea cucumber extract prevents damages induced by electromagnetic field on male sexual glands of mice.