The normal value of human total testosterone varies according to laboratory and examination methods, ranging from 14 to 25.4 omol/l in adult males and 1.3 to 2.8 nmol/l in adult females, and may vary slightly depending on age. Testosterone is a steroid produced in the interstitial cells of the human body. Testosterone is mainly produced by the testes in men and by the ovaries in women, and is the main androgen in the human body, and is closely related to the development of male secondary sex characteristics. Testosterone has the role of maintaining spermatogenesis and stimulating the growth and development of reproductive organs.