In the smart substation construction, SCD file will form different stage versions when communication parameters and virtual terminal are modified. This paper optimizes the comparison method and visualization method based on SCL. It proposes the comparison method based on standard middle process file and visualization method with four layers of humanized display. Through the extraction of different SCD files with key configuration information, from four level with IED, CRC, link, link parameters and virtual circuit. It implements the SCD file versions comparison layer by layer from top to down in a visual manner. It reduces the requirement on memory and CPU main frequency in the process of visualization comparison, improves the analysis and display efficiency of visualization, and provides convenience for operation and maintenance staff to carry out visualization management for the SCD file versions.