Cortisol, epinephrine and norepinephrine concentration in the antecubital and internal spermatic vein were measured and compared each other in 22 varicocele patients to investigate a possible toxic role of these materials to cause impairment of the spermatogensis. The results were as follow. 1) There were no significant differences of cortisol, epinephrine and norepinephrine concentrations between in the internal spermatic vein and in the peripheral vein, 2) Also in 6 patients who showed the abnormal findings on semen analysis and 7 patients who showed the impaired spermatogenesis on testicular biopsy, no significant differences of cortisol epinephrine and norepinephrine concentration were found between in the peripheral vein and in the internal spermatic vein. Therefore, cortisol, epinephrine and norephrine are not regarded as toxic materials responsible for the impairment of spermatogenesis in varicocele.