This study determines the density of the African nightcrawler earthworm (Eudrilus eugeniae) needed to obtain the maximum reduction in heavy metal content during the vermicomposting of cow, sheep, pig and chicken wastes in 90 days. The heavy metal studied a re zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), chromium (Cr), cadmium (Cd) and arsenic (As) cause of their toxicity effect on human health. Four batches composed of 5, 10, 15 and 20 individuals of Eudrilus eugeniae have been tested in 1 kg of cow, shee p, pig and chicken wastes and the variation of the heavy metal contents were measured at 0, 30, 60 and 90 days of the vermicomposting. The heavy metal content generally decreased when the number of individuals of E. Eugeniae increases. The lowest heavy met al concentration for each waste was obtained with 15 and 20 earthworms at 90 days of vermicomposting. Results of this study may help in the formulation of a strategy for vermicomposting with E. eugeniae.