Abstract:The mixed bacteria enriched from the acid mine water and soil in Shimian mining area of Sichuan Province was studied by mutagenesis with ultraviolet(UV), nitrosoguanidine(NTG), and their combinations as mutagen respectively, and then used to bioleach tellurium ore. The results suggested that the activity of the mixed bacteria increases 51.6 % with UV irradiation time being 5 min(15 W, distancing 30 cm). After treated by 1.0 g/L NTG for 50 min, the mixed bacteria showed higher activity, increasing by 57.4 %. The activities of mixed bacteria increased by 59.5% and 63.3% respectively with composite mutation. The bioleaching experiments showed that the maximum tellurium extraction rate by mixed bacteria after mutation had improved by 26.7% after 25 d of leaching.