Abstract: With the development of nonlinear statistical science,more and more theories have come into being,The fractal theory is one of them.Its application to the delineation of geochemical positive,negative anomalies not only guarantees the comprehensiveness of the original data,but also greatly improves the accuracy of the delineation range.In this paper,the northern half of 1∶50 000 map of Nachitai area is selected as the research area.Based on the original geochemical data,the paper uses the content-area method in the fractal method to delineate the positive and negative anomalies in the study area,achieving satisfactory effect,and at the same time,the superposition of the positive and negative anomalies is studied.According to the regional geologic and geochemical characteristics,and the positive and negative anomalies delineated by fractal theory,4 prospecting targets are delineated in the study area,pointing out the direction for next-step prospecting work.