Being an area that is frequently attacked by natural disasters, the Pearl River Delta is subjected to increasing serious impacts of lightning damages amid rapid growth of the economy. This paper analyzes the economic loss caused by lightning disaster occurring in the cluster of cities in the Pearl River Delta and the characteristics of the lightning disaster by quantitative analysis methods in order to fully realize the influence of lightning disaster on the national economy of Pearl River Delta. The study shows that the delta is an area with high frequency of lightning disasters in Guangdong province, where the frequency of lightning disaster is more than twice as much as the average of the province. The highest frequency occurs in Conghua and Zengcheng, northeast to the Guangzhou city, and the whole delta is an area of high frequency. The proportion of the loss caused by lightning disaster to those caused by natural disaster in the district is about 6% and even as high as 9.25% in years of the largest frequency. The loss caused by lightning disaster is much higher than the average level of 1.46% across the province. Lightning disaster becomes the forth disaster affecting the development of Peal River Delta, which causes an annual loss over 50 million yuan. The influence of lightning disaster on the national economy differs in different areas but has close relation with the frequency of lightning disaster and total regional economic value. The coefficients are 0.9 and 0.8 in the correlation between lightning-caused loss and lightning occurrences and total output of the national economy in the region, respectively, with the overall correlation being as high as 0.9665.