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It is important content of meteorological science and technology service to evaluate the return periods of climate extremes scientifically and reasonably, and it is of great significance to local economic development. For 35 kinds of climate extremes in Heze, by means of the Pearson Ⅲ, log normal, Gumbel, and Weibull distributions, the fittings of the climate extremes are conducted respectively. The optimal distribution functions are selected through χ2 test, and the climatic extremes of return periods are calculated through several return periods. Through the selection of the optimal distribution functions, the certain types of climate element subordinates to certain distribution function are studied. The results show that the extremes of the number of days and extreme temperatures are more likely obedient to the Pearson Ⅲ distribution, while precipitation and other extremes are more likely obedient to the Gumbel distribution. Some tips for using Excel calculation are introduced briefly.