In order to evaluate environmental effects of the chemical speciation of cadmium, the authors studied soils with high content of cadmium in Guiyang, and investigated the crop, water pollution and endermic diseases. Some conclusions have been reached: Cadmium is existent mainly in exchangeable fraction, residual phase, and Fe-Mn oxide phase, subordinately in weak organic combinational state and carbonate phase, and very lowly in water soluble phase. In vertical profile of soil,cadmium content decreases with increasing soil depth, cadmium is more concentrated in surface soil, and the distribution of chemical speciation of cadmium in deep soil is similar to that of surface soil. The water has not been polluted by cadmium in abnormal areas, and cadmium in such crops as rice, pepper and tobacco has exceed the state standard. In addition, local disease symptoms induced by cadmium has appeared in some areas. Therefore, the crops and human health are adversely affected by the high soil background values of cadmium in Guiyang, and the potential threat is serious.