Background: Male infertility affects 7% of males worldwide (i.e. 30 million of men). The diagnosis of the condition is based firstly on the semen analysis which can show various types of abnormalities. In Congo, data on male infertility are poor. This study aimed to determine the prevalence of male infertility in Brazzaville and to provide the profile of the semen parameters from a cohort of infertile men living at Brazzaville. Material and Methods: We studied semens of three hundred and forty-four (344) congolese men affected by infertility. The work was based on medical data to research medical history and the semen to performed the spermogram and spermocytogram in way to precise the sperm parameters, Results: The prevalence of male infertility found was 9% and the average age was 39 years old. Medical history highligts mostly the notion of chronic infection, varicoceles and surgery of the genital tract. The most identified sperm abnormalities were moderate asthenozoospermia followed by severe oligoasthenozoospermia and azoospermia. Conclusion: The prevalence shows that male infertility is not rare in Brazzaville. As the condition seemed to be related to the infectious, tumoral and professional causes, a complete investigation (based on sperm analysis, biochemical markers and genetic tests) is needed to clarify the etiologies.