This paper expounds Lewis Munford's urban theory and academic thought, significant for reference in our urban science research and urban planning and construction, with seven aspects: the cultural function of a city, the citizens' dominating role, the construction of city's cultural facilities, the urban renewal without demolishing all old buildings and the meaning of historical-cultural buildings, that it is not the larger the better for a city, the combination and intergration of city and countryside and the advocacy of going toward an ecological civilization.