The northern sub-belt of Western Qinling Orogen is endowed with abundant polymetallic resource. To delineate mineral exploration targets, a 1:25,000 stream sediment geological survey was carried out in the Changjiashan district. Statistical analysis was performed from 1,141 samples for Kernal Density Estimation elements (Au, Ag, As, Sb, Bi, Cu, Pb, Zn, W, and Mo). Element concentrations are higher than the national and regional average, indicating metallogenic potential in the area. Element combinations of the four factors were obtained based on factor analysis, i.e., F1(Bi-Cu-Zn), F2(Au-As-Sb), F3(Ag-Pb), and F4(W-Mo). We obtained thresholds of geochemical elements and factor scores, and geochemical mapping via Concentration-Area (C-A) fractal modeling and Kriging interpolation, respectively. Combined with regional ore-controlling factors and anomaly spatial distributions, three polymetallic anomaly areas, i.e., Hz1, Hz2, and Hz3, were delineated. Geochemical halos comprise the supra-ore halo, near-ore hole, and sub-ore halo from northwest to southeast. Distribution of stream sediment geochemical anomalies indicates that all mineralization was fault-controlled, and the area close to the NW-trending Lixian-Lüjing fault at Changjiashan represents a favorable prospecting target.