Research in sub-Saharan Africa has shown failures in most of municipal waste composting initiatives because of bad-quality composts due to the lack of biowaste source segregation. Until now, very few biowaste source-segregation initiatives have been carried out on this part of the world. This study aimed at assessing the biowaste sorting efficiency and the attitude of households towards a pilot biowaste source-segregation system linked to a decentralized composting plant in Tiassalé. For this purpose, the impurity rate of source-segregated biowaste was monitored through the first year of implementation. Then, a cross-sectional survey was conducted to evaluate households' attitude. The results have shown that the average impurities rate in source-segregated biowaste was very low (1%). This finding was confirmed by the results of laboratory analysis which revealed a very low heavy metals (0.2, 12.4, 7.1 and 15.5 mg kg