The Caizihu Lake line, one of the important water delivery lines of the leading water project from Yangtze River to Huaihe River, was selected as the research object. The pollution level, distribution characteristics and ecological environment risk of 12 kinds of organophosphorus pesticides (organophosphorus pesticides, OPPs) in the water and sediments along the line were tested and analyzed. The results showed that the total concentration of OPPs ranged from 112.8 to 1 781.4 ng/L in the water, mainly in bromophos, carbophenothion, and ethoprophos; and ranged from 290.33 to 13 105.25 ng/g in the sediments, mainly in ethoprophos, sulfotep and chlorfenvinphos. Compared with those in water and sediments from other areas in China, the main types of OPPs pollutants in the Caizihu Lake line are quite different. The results of the ecological risk assessment of OPPs in the water showed that bromophos, carbophenothion, and chlorfenvinphos showed high ecological risks (RQ > 1) in the entire ofCaizihu Lake line, much higher RQ of OPPs risks appeared at C, D, H, and K these four sites (RQ > 10 000), and dichlorvos and sulfotep in most observed sites showed mediμm (0.1 < RQ < 1) or low ecological risk (RQ < 1). The results of this study will not only provide the necessary basic data for the long-term tracking and evaluation of the ecological quality of the water environment along the Yangtze River to the Huaihe River, but also provide a scientific basis for assessing the health risks.