Introduction: Acute diarrhea is one of the leading causes of mortality and morbidity in children under 5 years old. Globally, it is responsible for around 4 million hospitalizations and 1.1 million deaths per year. Various etiological agents are implicated, including the viruses which constitute the 1st cause, mainly the rotavirus of group A. The prevalence of rotavirus diarrhea is estimated at 38% globally, 34% in Africa and 62.7% in DRC. The objective of this study is to determine the hospital prevalence of rotavirus diarrhea in children under 5 years old, and to identify circulating genotypes. Methodology: This is a cross-sectional descriptive study, carried out over 6 months in the pediatric emergency department at the HGR / Panzi. 68 fresh stool samples were collected and stored at the medical school research laboratory. Detection of rotavirus was achieved through the use of the enzyme-linked immunosorbent assay ELISA technique and genotype determination by RT-PCR. Results: The prevalence of rotavirus gastroenteritis was 42.6%; Its frequency was highest in children under 24 months, who were the most affected, of which the 0-6 month group represented 37.9%, followed by that of 7-12 months (31%) and 13-24 months (27.6%).The associated factors were the age of our patients, the environment of origin, the level of education of the mothers, the feeding method of children (p <0.05). The clinical signs associated with diarrhea were vomiting (34.48%) and fever (31.03%); The G1 genotype represented 21%, followed by G2 (7%) and G3 (3%); two P genotypes have been identified P [8] and P [4]. Conclusion: Rotavirus remains an important cause of acute diarrhea in children under 5 in our region as well as in the Democratic Republic of Congo. The introduction of the vaccine into the national immunization program will reduce its frequency somewhat.