The authors conducted 1:50 000 rock structure geochemical survey in the Yiliu orefield of northern Guangdong. Structural fissure filling material, mineralized altered rock, ore veins and limonitization as the sampling media, ore-inducing geochemical anomalies could be effectively delineated, and the delineated anomalies were basically consistent with the stream sediment anomalies in spite of the existence of some differences in anomaly size and intensity. The results show that rock structure anomalies are obviously more consistent with the known ore deposits (ore spots) than stream sediment anomalies. Due to the limitation of the sampling conditions, this method is only suitable for areas with well exposed basement rock and areas dominated by limestone. This method has reference value for geochemical exploration in strongly weathered, thickly covered areas dominated by limestone in southern China.