Geoaccumulation index(lgeo) and Lars Hakanson potemtial ecological harm index are used to evaluate and compare the ecological hazard of heavy metal on the soil of abandoned Mn mines in Southern Hunan and the results show that the heavy metal pollution at the soil of the abandoned Mn mines is serious,that the lgeo of both Mn and Cd is beyond 5,that Mn,Pb and Cd are main heavy metals for the hazard on production and ecology in this area,that the pollution order if the five metals is Cd>Mn>Pb>Cu>Zn,and that the potential ecological harm index of the two evaluation methods is of real significance.According to the research results of dry land at the downstream and the crops planted in the land may be polluted by the heavy metals and the food from the crops should not be eaten.