The aim of this study was to confirm the presence of soluble interleukin-6 receptor (SIL-6R) in seminal plasma, to show eventual differences between SIL-6R concentrations in fertile and infertile men, and to evaluate the possible value of measuring these substances for the diagnosis of male accessory gland infection. SIL-6R levels were determined by "sandwich" enzyme immunoassay in the seminal plasma of 82 men divided into 7 groups according to the etiological diagnosis of fertility. The levels of SIL-6R in the seminal plasma of men with infection of the accessory genital glands were statistically significantly different in comparison with other groups (p < .001). The results suggest that urogenital infections may lead to elevated levels of SIL-6R in the seminal plasma. This measurement of SIL-6R in semen may provide clinically useful information for the diagnosis of male accessory gland infection.