The data from the RegCM4 model under the RCP45 scenario based on the quantitative and the qualitative assessments are selected to project the annual mean precipitation, mean, maximum and minimum temperature over Guizhou during the period of 2018 to 2050 Results show that the annual mean precipitation over Guizhou would become 85% less than that during the base period with the greatest magnitude over the north part in the first stage of the 21 century (2018 to 2028). Less rainfall would occur over the midwest and more over the eastern regions in the second stage of the 21 century (2029 to 2039) with a magnitude of 7%, while the rising tendency would be greater over northwestern regions and less over the south and east regions during the third stage of the 21 century (2040 to 2050) with a percentage increase of 75%. The annual mean, maximum and minimum temperature would increase by 06 to 13 ℃ comparing to the baseline in the first, second and third stage of the 21 century. The temperature rise would be proportional to time with less differentiation from place to place.