Abstract: Comparative analysis of the lightning location data from 2009 to 2013 is conducted by temporal and spatial distribution and detection efficiency, to explore the difference of data collected from two lightning location systems (LLS) of Zhejiang meteorological department and Zhejiang electric power department. Results show that the inter-annual cloud-to-ground (CG) lightning frequency observed by the LLS of Zhejiang meteorological department is stably lower than that observed by the LLS of Zhejiang electric power department. The number of positive CG lightning occupies 3.5% of total CG lightning observed by the LLS of Zhejiang meteorological department, which is also 2% less than that observed by the LLS of Zhejiang electric power department, and both of them are in a reasonable interval. From the viewpoint of spatial distribution, the CG lightning density of two datasets is nearly equal in coastal plain and the Jinhua-Quzhou Basin, but the CG lightning density obtained by Zhejiang electric power department is stably more than that of Zhejiang meteorological department in the other areas except in Chun'an which is located in the border of Hangzhou and Quzhou. It is also found that the occurrence of high CG lightning density region in Chun'an observed by LLS of Zhejiang meteorological department is abnormal. Further analysis of the number of monthly mean thunderstorm days obtained by these two LLSs and manual observation indicates that the monthly mean thunderstorm days observed by the LLS of Zhejiang meteorological department is not more than that of manual observations except in summer, when the monthly mean thunderstorm days observed by LLS of Zhejiang electric power department is almost more than that of manual observations every month. It suggests that the LLS of Zhejiang meteorological department does well in detecting strong thunderstorms while the weaker thunderstorms could be missed. Hence, the LLS detective ability of Zhejiang electric power department is better than that of Zhejiang meteorological department. On the other hand, comparative analysis of detection efficiency is made based on the data of accidents of lightning trip-out on Zhejiang Power Grid. It is concluded that the detection efficiency of the LLS of Zhejiang electric power department is around 6% higher than that of Zhejiang meteorological department.