The present study focused on the analysis of the risk factors of diarrhea in Southern Benin. Data have been collected from 442 peasant households on the basis of a stratified random sampling method in the targeted communities, with information on the source of water provision, the location of the village, the usual defecation place, the site of refusing dumping and the presence of trash dump in the vicinity of the household. Data have been analyzed using descriptive statistics. In addition, analyses of variance and log-linear analyses have been applied to test the various factors in the outbreak of diarrheas. Results have allowed a hierarchical organization of the drinking water sources with regards to their use and to the cases of diarrheas (boreholes: p < 0.001; rainwater and territorial water: p < 0.001; wells: p = 0.547 and pipe-borne water: p = 0.277. If we rule out people’s insanitary behaviors, the impact of some risk factors such as the sites of waste disposal (2%) and excreta disposal (1%) is of little influence in comparison to the water supply source and the place of residence, which play respectively for 62% and 30% in the outbreak of episodes of diarrheas in households. It follows that, to curb the diarrhea morbidity, there is the need to improve the water supply policy and the environmental sanitation.