Abstract: The historical data of drought and flood contain comprehensive and reliable environmental information, which records the frequent occurrence of natural disasters in China during the Little Ice Age. However, researches on the climatic and environmental conditions and their impacts on human activities in Guizhou region which use these data are few reported. This paper collated and analyzed the historical data of drought and flood in the area of Guizhou from 1470 to 1949, verifying by correlation analysis based on mutual information, exploring the humidity variation processes and cycles by sliding average method and wavelet analysis, , discussing its controlled mechanism and the influence on human activities compared with the high-resolution stalagmite δ18O sequence, ocean thermal condition and the relationship between central and local governments. Results showed that（1) the climatic condition in Guizhou was dry in the late 15th century, while in the 16th century it was wet. After the dry period in the early 17th century, Guizhou experienced a long and stable wet period which was from the mid-17th century to the early 20th century. These results correspond well with copious records.（2) The humidity variation had periods of about 128~155 years, 32~55 years and 11~20 years, reflecting that they are primarily controlled by solar radiation intensity and solar activity.（3)The humidity variation was affected by the intensity of the South Asian summer monsoon, ENSO and AMO as well as solar radiation, which also had profound impacts on political activities and other human activities during Ming and Qing Dynasty.