Abstract: Taking West Tianshan metallogenic belt as an example, based on regional geochemical data,geochemical fields,geochemical regions and subregions are divided, geochemical characteristic is expounded. By studying the distribution of geochemical anomalies, using geochemical parameters Mean Square Errorand Anomaly Threshold which relate to geological mineral evaluation., combining Average Value and Area of geochemical anomaly, built the concepts of Prospecting Favorable Degreesand Quality of Mineral which are used for quantitative description of the extent and potential of each geochemical anomalypotential amount of resources.Throughestablishing typical models of deposits, by analogy of deposit model and geochemical anomaly, comparing the predicted results with the known mineral resource,consider that using the Quality of Mineralto quantitatively describe the ore potential of multi-elementary anomaly is a viablemethod of prospecting potential evaluation.