By experimental study of release characteristics bottom silt of total nitrogen (TN) & total phosphate (TP) in the Three Gorges, the influence and cause of pH value to Three Gorges bottom silt TN & TP release are analyzed. pH values is between 3.98 to 11.05 the release capacity of TN & TP reaches maximal in 3 days and pH values is between 11.05 to 11.94 the release capacity of TN reaches maximal in the 3 days. While pH value between 11.05 to 11.94, the release capacity of TP reaches maximal in 1 days; If pH value is lowered, the maximal release capacity of TN is enhanced: The maximal release capacity of TP basically has no changes on the condition of pH values between 3.98 and 10.07, but its maximal release capacity rises extremely obvious if pH value is between 10.07 to 11.05. At the same time, the existence of latent danger of the Three Gorges bottom silt TN & TP to water quality is explained, and the basis of eutrophication treatment in the aspects control of N & P nutrients for theThree Gorges is supplied.