Introduction: Low birth weight is a public health problem because of the morbidity and mortality associated with it. The aim of this study was to identify the factors associated with low birth weight in Bukavu.Material and Method: This was a case-control study including all live and full term births during the period from January to December 2015 in the maternity wards of 3 general reference hospitals in Bukavu. The cases included all the full term newborns weighing less than 2500 grams and they were compared with control group corresponding to full term newborns weighing 2500 grams or more.Results: In full term newborns, the prevalence of low birth weight was 11.6%. Inter pregnancy interval less than 24 months, infection during pregnancy, anemia during pregnancy, high blood pressure, maternal age less than 18 years, mother schoolgirl were the factors associated with low birth weight.Conclusion: The prevalence of low birth weight is high in Bukavu. Identified factors associated, in full term newborns included short inter pregnancy interval, infection during pregnancy, anemia, high blood pressure and schoolgirl. In order to reduce the negative impact of these factors on birth weights, the current preventive strategies should be strengthened particularly the activities of the prenatal visits or supplemented by others including intensive sensitization for the use of contraceptive methods as well sex education to young adolescents.