With the development of social economy and promotion of industrialization and urbanization, the urban ecological environment has been deteriorating. Therefore, more attention has been paid to the residential ecological environment. The assessment of residential ecological environment is crucial, as it can provide scientific basis for urban development planning, environmental planning, as well as the allocation of the urban real estate projects. Through principal component analysis, this paper developed a quantitative analysis on the quality and spatial pattern of residential ecological environment in the central city of Hangzhou. The results suggested that the residential ecological environmental quality decreased in a gradient from scenic tourist spot to urban central area and industrial area. Vegetation, traffic, land surface temperature, population density and air quality were key factors that had influenced residential ecological environment, and played an important role in determining the overall pattern of residential ecological environment. Meanwhile, industry density and water coverage had large impact on the residential ecological environment of some districts. As good residential ecological environment was important to strengthen the competitiveness of Hangzhou, measures need to be adopted to protect and repair fragile zones of residential ecological environment according to the characteristics of the key impact factors.