To sample in the primary halo in the alteration which is controlled by two structures, granodiorite in 300 m of middle part of Sandaogou gold deposit, through the contrastive analysis of microelement of unaltered granodiorite, gold ore and diabase. It is determined that alteration belt should be mineralized alteration belt, the ore body was discovered along the alteration belt;sampled in primary halo along the faulted structure, NE ore-controlling structure of Shiren gold deposit, in high Au, Hg element area, the ore body was discovered. At the beginning of the exploration that partial understand primary halo zoning of ore deposit. This is a simple, economical prospecting method using structural primary halo one.