BACKGROUND: In low income countries, mental disorders are a neglected health problem. Mental disorders are influenced by a number of factors in people's everyday life of which intimate partner violence (IPV) commonly form an important part. The aim of this study was to investigate the prevalence of mental disorders in young men and women in Rwanda and their risk factors with main emphasis on IPV and its contribution to mental disorders, taking into account the genocide context. METHODS: This population-based study included a representative sample of 917 men and women aged 20-35 years. The prevalence of mental disorders was investigated using of a diagnostic tool, the "MINI: Mini International Neuropsychiatric Interview". Risk factor patterns were analysed with bi- and multivariate logistic regression. To find the proportion of mental disorders attributed to IPV, the population attributable fraction was computed. RESULTS: The prevalence rates of current depression, suicide risk and PTSD were more than two times higher in women than in men while for generalized anxiety disorder, the prevalence was about the same. Physical, sexual and psychological intimate partner violence exposure was highly associated with all forms of mental disorders for women. For physical violence, after adjusting for socio-demographic factors and exposure to traumatic episodes during the Rwandan genocide, the risk of current depression for women was elevated four times. Even though few men reported partner violence exposure, physical violence in the past year was found to be a statistically significant risk factor for current depression and for generalized anxiety disorder. However, having an experience of traumatic episodes during the genocide contributed to the risk of most of mental disorders investigated for men. CONCLUSION: In Rwanda, IPV contributed considerably to mental disorders investigated. Thus, prevention of IPV should be considered as a public health priority, as its prevention would considerably reduce the prevalence of mental disorders.