In order to Role of earthworm on bioremediation of heavy metals (lead and cadmium) in two varieties of maize (zea mays L.), an experiment was carried out at Sari, Mazandaran, Iran in 2010. Experiment was arranged as factorial design based on random complete block design and was conducted with pots with three replications and treatments were chosen earthworm (E0= without earthworm and E1= with earthworm), heavy metals of lead and cadmium (0, 150 and 300 mg/kg). Result showed that earthworm number decreased by increasing of heavy metals levels. According to the results, number of earthworm decreased by increasing of pollution level that it caused by increase of lead metal level. Focus of heavy metals in earthworm enhanced by increasing of heavy metals level (cadmium and lead) but lead was more absorbed by earthworm compare to cadmium. Tolerance index demonstrated 53% decrease compare to control by increasing of lead (pb300) and it was 56% decrease for cadmium (cd300) compare to control and it means plant had more tolerance in lead compare to cadmium. Amount of heavy metals concentration in seed increased by enhancing of lead and cadmium in soil. Application of more heavy metals showed more concentration in the soil. Maximum concentration was related to lead (pb300) soil that demonstrated 14 % increase compare to cadmium.
