Abstract: Lightning disaster has been one of the serious disasters affecting the development of economy and society. Based on information diffusion theory, the model of lightning disaster risk assessment is established. And the lightning disasters from 2008 to 2019 in Jiangsu province are analysed by this model. The results show that lightning disasters have been mainly concentrated in 320 times per year, about once every 1.9 years. The probability of more than 880 times per year is low, about once every 38.2 years in Jiangsu province. The risk of life injury and death has been mainly concentrated in 12 people per year, about once every 1.8 years. The number of casualties for more than 30 people per year is about once every 14.1 years. Then the cumulative probability of economic loss with the risk value of 6.50 million yuan per year is 58.62%, but the probability of 22.50 million yuan per year is very low, only 1.84%. Through quantitative calculation and analysis, a deeper understanding of lightning disasters is achieved and the scientific basis for the government departments to make disaster prevention and mitigation decisions is provided.