<p><b>OBJECTIVE</b>To evaluate the effects of the Chinese herbal formula Wuzi Yanzong Pill (, WYP) on the spermatogenesis and specific secretory functions of Sertoli cells in rat model and to investigate the underlying mechanism.</p><p><b>METHODS</b>Five groups of male Sprague-Dawley rats including the control group, the model group, the low-dose WYP group, the medium-dose WYP group and the high-dose WYP group (5 in each group) were treated daily with vehicle, multiglycosides of Tripterygium wilfordii Hook f (GTW) either alone (20 mg/kg) or followed by WYP (0.5, 1.0, or 2.0 g/kg daily), respectively for 30 days. Serum levels of follicle-stimulating hormone (FSH), inhibin B (INHB) and testosterone (T) were evaluated using enzyme-linked immunosorbent assay. Androgen-binding protein (ABP) gene expression and transferrin (TF) protein expression in testis tissue specimens of all rats were determined using real-time reverse transcriptase polymerase chain reaction and Western blotting analysis, respectively. Histopathological alterations in the testis were determined using Johnsen's score.</p><p><b>RESULTS</b>The toxicity of GTW towards Sertoli cell secretory functions and spermatogenesis was accompanied by increased serum FSH concentrations and decreased INHB and T concentrations. Upregulated ABP mRNA levels, and decreased TF protein expression and Johnsen's scores were detected in the model group compared with the control group P<0.05 or P<0.01). Oral high-dose WYP administrations to GTW-treated rats effectively alleviated all of the GTW-induced changes in specific secretory functions of Sertoli cells (ABP, INHB and TF). Furthermore, serum T level and Johnsen's score of the testis increased greatly compared with the model group (P<0.01).</p><p><b>CONCLUSION</b>WYP has the ability to improve the spermatogenesis, possibly through modulating the secretory proteins expression of Sertoli cells.</p>