In order to provide a climate proof for Adjusting protection scope of china geographical indication of Jietan tea, Applied agricultural climate similarity analysis methods such as Similarity coefficient method, Euclidean distance method and Climatic quality analysis method, Analysised Climate similarity of core area and those towns of the protection scope is to be expanded,concluded: the various climate similarity coefficients of the core area and the each towns to be expand are tested by significance correlation, the Euclidean distance of most towns and meteorological factors is highly similar. The climatic quality index of tea leaves in different towns is similar to that of core area,and quality is good. In conclusion, The climate conditions of tea grown in the core area and those towns to be expand are highly similar. From the climate point of view, We can expand the protection scope of china geographical indication of jietan tea.