Abstract: This article generally assumes that runoff data have the same frequency as the rainfall data since runoff data is hard to be monitored and measured in the long run whereas rainfall data is easier to be collected.Based on the assumption,hydrology analysis of rainfall data was discussed in the article.To ensure precise analysis,and fully characterize actual rainfall data effectively,a method of rainfall analysis based on Copula function was introduced in the article.Characterizing multiple rainfall variables,and using the history rainfall data of Guangzhou from 1961 to 2012 as an example,the method revealed an effective application for the combination analysis of various rainfall character variables,and a perfect fitness of the inner needs of hydrology analysis.Furthermore,the discussed method fully indicated rainfall data characters,and improved the accuracy of analysis calculation.