The relationship between the interleukin (IL)-11 levels and semen quality of infertile males remains unknown. In this study, 120 semen samples from 60 normozoospermic volunteers and 60 infertile males were examined. The semen pH of the normozoospermic group was not significantly different from that of the infertile group. The semen volume, semen density, forward movement percentage, activity, survival rate and normal morphology rate of the sperm of the infertile group were significantly lower than those of the normozoospermic group. The semen IL-11 levels of the infertile group were significantly lower than those of the normozoospermic group. In the infertile group, semen IL-11 levels were positively correlated with sperm motility, vitality, survival rate and normal sperm morphology rate and negatively correlated with IL-17 and IL-18 levels. Therefore, semen IL-11 levels could be used as an index of male infertility.