To explore geographical differences in quantitative characteristics and spatial pat-tern of human settlements environmental suitability (HSES) in the Three Gorges Reservoir Area (TGRA), terrain, climate, hydrology, vegetation and other natural factors were selected to build the livable environmental evaluation, and the quantitative analysis was conducted through Remote Sensing(RS) and Geographic Informational System (GIS) to reveal geo-graphical characteristics and spatial patterns of HSES. The results are obtained as follows: (1)inhabitants of the TGRA of Chongqing are concentrated in the area with moderate h.igh HSES,which is 78% of the total population distributed in 48% of the study area; (2) the HSES is closely related to the terrain, and it forms an arc-banded spatial succession pattern: relatively low in the northeast and the southeast while comparatively high in the west and the south; (3)large numbers of people are distributed in the area with low suitability (with higher population density than the average of the western China), but economic development level in these areas is quite low. Moreover, these areas are ecological sensitive and fragile, many kinds of eco-environmental problems have been caused by human activities. Therefore, population migration and layout are reasonable options for the development of these areas.