In July 2020，the quadrennial election for governor of Tokyo was held. Under the the impact of the COVID-19 epidemic，more than 20 candidates including the current governor Koike Yuriko participated in the election，and finally Koike won the re-election. The main reasons for Koike’s victory in the election include the stable governing performance，a positive image in epidemic prevention，success in manipulating public opinion，support from major political forces in Tokyo and the lack of competitiveness of the opposition parties. The result of that election will be beneficial to the election of the Koike’s “tomin-first” party in the 2021 Tokyo Metropolitan Assembly Election；the tension between Koike and the Liberal Democratic Party will be temporarily relaxed，however，it is still unlikely that she will participate in the parliamentary election. In addition，the growing trend of populism in Japan reflected in that election deserve our further attention.