This paper examines the difference in the pattern of development of the Cultural Revolution in Beijing and Shanghai, two cities. During the Cultural Revolution, the violence began in Beijing, where has a history of the revolution. Moreover, it bad been strongly influenced by the lack of education, the ``Square effect``, and psychological status of the field in Beijing. The Author concludes that the difference of two cities in the Cultural Revolution came from the difference of their local cultures. This calls us to recognize the importance of a city-based approach of the local politics in the analysis of the Cultural Revolution.