On the basis of previous work, the authors collected 1:200 000 regional geochemical data along the northern margin of Qaidam Basin,used fractal (multifractal) method to determine geochemical anomaly characteristics in Gobi desert area of eolian sand, and adopted the C-A and S-A model to investigate the characteristics of geochemical anomaly of Au element influenced by eolian sand in the Gobi desert area. The results show that C-A model has advantages in determining the threshold but still has some limitations. S-A model can well eliminate the background field and interference factors, reduce the area of anomaly, and can make prominent the small weak anomaly. The method of extracting the region of anomalous elements can be used to identify the vast majority of known ore deposits and indicate the further anomal anomaly area of ore-forming elements based on the geochemical data, thus providing a reference for further exploration.