Abstract: Taking the data of agricultural microclimate in the towns and communes of Jian County,Jilin Province as an example,in this articlea preliminary attempt has been made in the classifica-tion of agroclimate with the theory of fuzzy mathematics and its method.Fuzzy mathematics is a way of dealing with fuzzy phenomena;especially in microregions(under the level of county)where the lack of experimental and observational data is apparent,it has more significance of practicality to apply the concept of fuzzy sets to the analysis of climate.This article highlights an exposition of the procedure of fuzzy clustring analysis and its application in the classification of agroclimate as well as a few points of personal experience in the preliminary study and research.It was proved in practice that the fuzzy clustering analysis can mere objectively reflect the quanfifafive relationship of various climatic regions,and that in applying this method to the classification of agroclimate microregion,the logical deduction is reasonable,the methodology is simple and convenient;the classifica-tion is plain and the system of classification is clear.