Municipal solid waste (MSW) landfills without any soil protection constitutes an environmental risk factor in particular heavy metal pollution. These sites, located close to inhabitants, can induce contamination through the food chain. The present work aims to be a contribution in measuring heavy metals concentrations generated by unsorted waste dumped from 1983 until 2008 on Buterere open air landfill in Bujumbura to assess soil contamination, pollution levels and health risk. Materials used are soil samples collected from 15 points at the Buterere site. The physicochemical characterization of the soil was carried out by thermogravimetry (TGA) and X-ray diffraction (X-RD). The determination of heavy metals was carried out by X-ray fluorescence (X-RF) and Inductively Coupled Plasma atomic Spectroscopy-Optical Emission (ICP-OES). Chronic carcinogenic and non-carcinogenic risk indices were evaluated based on experimental results in order to formulate adequate prospects for remediation. Results show that the heavy metals are not homogeneously dispersed on Buterere site but their concentration levels do generally exceed the limit values (World Health Organization, European Union). A significant correlation (p <0.05) was demonstrated for the simultaneous presence of the micropollutants of Cd, Cu, Fe and Zn in the study area. Based on these results, the health risk assessment reveals that the Buterere site can induce carcinogenic and non-carcinogenic nuisances to the population in its and therefore remedial measures are proposed.