Male infertility constitutes a worldwide problem, especially in Nigeria where most men do not readily accept that they may contribute to the couple's infertility. In order to assess hormonal disturbances in the male infertility we compared male reproductive hormonal levels in human serum and seminal plasma and evaluated the hypothalamic-pituitary-testicular-axis in infertile Nigerian males. The biophysical semen parameters were assessed by W.H.O. standard manual method. Serum and seminal plasma male reproductive hormones (Leutinizing hormones, Follicular stimulating hormone, Prolactin and Testosterone) were measured by Enzyme Immunoassay (EIA) technique of W.H.O. in sixty (60) infertile adult male Nigerians (Oligospermic; n = 40 and azoopermic; n = 20) and forty controls of proven fertility (Normospermic subjects; n = 40). The results show that the serum concentrations of gonadotropins (LH and FSH) were significantly higher (P<0.05) in infertile subjects than controls. Patterns of serum prolactin levels were similar. The values of gonadotropins in serum were significantly higher (P<0.05) than those of seminal plasma. Seminal plasma testosterone in infertile subjects was significantly higher (P<0.005) than that of controls but the serum levels of testosterone were significantly higher (P<0.05) in azoospermic than oligospermic subjects and controls. There was no significant correlation between serum hormonal level and seminal plasma hormonal level in all the groups (P<0.05). We concluded that male infertility in Nigerians is characterized by hyperprolactinaemia, raised serum gonadotropins (LH, FSH), and raised seminal plasma testosterone. Hormonal profiles in serum and seminal plasma were not significantly correlated, and hence cannot be used as exclusive alternative in male infertility investigations. The observed spermogram in spite of significant elevation of seminal plasma testosterone in infertile males investigated suggests Sertoli cells malfunction.