Background and Objective: The spathe of phoenix dactylifera contains protein, fatty, fiber, sugar, moisture, furfural, coumarin, organic compounds of camphor family, phytosterols, 1, 2-Di methoxil 1, 4-Di methyl benzene. This study was done to evaluate the effect of alcoholic extract of phoenix dactylifera spathe on seminiferous tubules and spermatogenesis in adult male rats. Methods: In this experimental study, 50 adult male rats were randomly allocated into five groups including: control, sham and expermintal groups 1, 2 and 3. Animals in control group did not receive any treatment. Animals in sham group were received 0.2 ml normal saline intraperitoneally. Animals in experimental group 1, 2 and 3 were received 0.05, 0.1 and 0.2 g/kg/bw of alcoholic extract of phoenix dactylifera spathe intraperitoneally, respectively. After 14 days of study, the testis was removed and the sections of tissue were prepared. Testosterone hormone measured by Gamma counter method. Results: Serum levels of testosterone and the spermatozoa count were significantly reduced in the experimental groups in compared to control and sham groups (P<0.05). The count spermatogonia, primary spermatocyte, spermatid, sertoli and leydig cells and seminiferous tubules structures did not reduce in the experimental groups in compared to control and sham groups. Conclusion: Phoenix dactylifera Spathe alcoholic extract at doses of minimum and medium in adult male rats reduces sera level of testosterone and spermatozoa number.