As an important geophysical tool，high density electrical technique infers the underground geological structures by processing and inverting the apparent resistivity data． Currently，the false anomalies have been frequently occurred in the graph of apparent resistivity pseudo- section or inverted geoelectrical section obtained from high- density electrical technique，and are difficult to remove． In this study，the authors explain the mech- anism of the false anomalies and put forward the horizontal differential field method to identify the false anoma- lies． Based on the analysis of modeling results，this method is applied in the surveying data in Xinlei Quarry of Jiuquan，and the results confirm the effectiveness of the horizontal differential field method．