Abstract: The serum concentrations of hCG were paralel to the injection dosages, with a around 85h of half-life for elimination. The response of testosterone to hCG presented a biphasic curve with the main secretory peak at the point of 72h. It was thought that while stimulation test, single injection of hCG was more rational than one injection every day for a few days, and while the rapeutical application, one injection every 5 to 7 days in dose of 1000 to 2000u was suitable.