Based on the ecological survey, the ecological indexes of microorganisms, physico-chemicals and chlorophyll-a was measured on the water source area of the middle-line project of Transferring Water from South to North, 2005. The result showed that the nutrition type of the water source could be regarded as mesotrophyic;Danjiangkou Reservior is suitable for water source because the indexes except TN belong to the standards of Grade I water. This study would provide scientific information for data bank of long-term ecological research on middle-line project and policy of ecological environmental protection