Considering the conditions of temperature, humidity, wind speed and sunshine duration, the temporal and spatial distribution of temperature-humidity index(THI) and wind effect index(K) were calculated at 22 weather stations in the Three Gorges Reservoir catchment from January, 1995 to December, 2010 based on GIS technology. The general distribution trend on climate suitability for human settlement in Three Gorges Reservoir was analyzed. The change in climate suitability for human settlement was analyzed before and after impoundment based on the first storage stage of the Three Gorges Project in June, 2003. Correlation analysis of water level and meteorological elements were also investigated. Results show that the climate is not comfortable from November to March in the next year due to the cold temperature. Similarly, the climate is also not comfortable from June to September due to the hot weather. The average annual THI and K exhibit obvious regional difference. The integrative trend of THI and K decreases progressively from central to east and west areas. Climate suitability has changed obviously since the accomplishment of the Three Gorges Project. The results of Pearson's correlation coefficients showed no correlation between THI, K and water level before June 2006, whereas water level showed significantly positive correlation with THI and negative correlation with K after that time.