Based on monthly runoff data of Hongjiadu,Guizhou from October 2013 to June 2015 and monthly runoff data of Yachi River,Guizhou from April 2014 to May 2015,using REOF and multiple linear regression analysis,regulation effect of water conservancy project in upper reaches of Wujiang River on monthly runoff of the river was analyzed. Seasonal temporal-spatial change of monthly runoff in Hongjiadu and Yachi River mainly contained two kinds of modalities. The first modality was that of Yachi River,which was main component of seasonal change of monthly runoff,and peak appeared in July. Space load of Yachi River modality was larger than Hongjiadu,and manual control ability of monthly runoff in Hongjiadu was larger than Yachi River. The second modality was that of Hongjiadu,and peak appeared in December. Space load of Hongjiadu modality was larger than Yachi River,and manual control ability of monthly runoff in Yachi River was larger than Hongjiadu. Seasonal changes of time components of two modalities had significant inverse phase. Regulation effect of Hongjiadu modality advanced Yachi River modality,and regulation effect of water conservancy project in Hongjiadu modality was larger than that of Yachi River modality,and seasonal distribution characteristics of regional rainfall was basically eliminated in Hongjiadu modality. Some seasonal distribution characteristics of regional rainfall were maintained in Yachi River modality. Monthly runoff modality of Yachi River had water storage regulation effect on a smaller part of regional monthly rainfall modality. Monthly runoff modality of Hongjiadu mainly had water storage regulation effect on south-north type of component of regional monthly rainfall,while most components of regional monthly rainfall modality did not have significant impact on monthly runoff modality of Hongjiadu. Based on monthly runoff data of Hongjiadu, Guizhou from October 2013 to June 2015 and monthly runoff data of Yachi River, Guizhou from April 2014 to May 2015, using REOF and multiple linear regression analysis, regulation effect of water conservancy project in upper reaches of Wujiang Seasonal on-month change of monthly runoff in Hongjiadu and Yachi River mainly contained two kinds of modalities. The first modality was that of Yachi River, which was the main component of seasonal change of monthly runoff, Space load of Yachi River modality was larger than Hongjiadu, and manual control ability of monthly runoff in Hongjiadu was larger than Yachi River. The second modality was that of Hongjiadu, and peak appeared in December. Space load of Hongjiadu modality was larger than Yachi River, and manual control ability of monthly runoff in Yachi River was larger than Hongjiadu. Seasonal changes of time components of two m Regulation effect of Hongjiadu modality advanced Yachi River modality, and regulation effect of water conservancy project in Hongjiadu modality was larger than that of Yachi River modality, and seasonal distribution characteristics of regional rainfall was substantial eliminated in Hongjiadu modality. Some seasonal runoff modality of regional rainfall were maintained in Yachi River modality. Monthly runoff modality of Yachi River had water storage regulation effect on a smaller part of regional monthly rainfall modality. Monthly runoff modality of Hongjiadu mainly had water storage regulation effect on south-north type of component of regional monthly rainfall, while most components of regional monthly rainfall modality did not have significant impact on monthly runoff modality of Hongjiadu.