Because of the extremely uneven distribution of gold in the samples and bad representativeness of samples in the coarse-grained gold ores,which cause errors far greater than those from sample processing and analysis,it is impossible to accurately evaluate the grade of this kind of ore.In this paper,gold mine in 3 different areas (Changgou and Jindoupo from Hanyin,and Yangpingwan from Shiquan) of the coarse-grained gold ore belt in northern Ankang,Shaanxi Province,were selected.Samples were collected with 5 different sampling specifications,including 10 cm×5 cm,10 cm×10 cm,20 cm×3 cm,20 cm×5 cm and 20 cm×10 cm.The gold grade in heavy and light minerals was analyzed with heavy fraction method.The results show that the sampling specification has obvious influence for the gold grade from the same sampling point,but large-scale sampling does not exhibit more representativeness.Meanwhile,small-scale sampling shows higher gold grade than large-scale ones;sampling points have significant influence on gold grade,especially in Jindoupo and Yangpingwan Gold Mine.The sampling spot choice is extremely important.To ensure the representativeness of sampling,the sampling specification is best to be 10 cm×5 cm and the sampling weight be 15-20 kg.