The effects of the rice-duck-crayfish integrated model （RDCI） on the water quality，continuous sampling and testing of water in RDCI，rice-crayfish continuous culture model （RCCC） were studied at the Shuangshui Shuanglü Research Base in Xingou Town，Jianli City from March 2023 to January 2024.The differences in the changes of water physicochemical factors during different stages including crayfish farming stage，rice regreening stage，rice-duck co-cultivation stage，rice mature stage，and overwintering stage for the two models were analyzed.The results showed that the range of annual variation in water temperature，dissolved oxygen，and pH in RDCI was 3.23-33.50 ℃，2.42-11.75 mg/L，and 7.18-8.32，basically consistent with that in RCCC.The range of annual variation in the content of total nitrogen，total phosphorus，ammonia nitrogen，nitrate nitrogen，and COD_Mn in RDCI was 0.54-2.12 mg/L，0.13-0.50 mg/L，0.16-0.56 mg/L，0.06-0.40 mg/L，and 5.58-18.35 mg/L，having an overall trend of first increasing and then decreasing and a peak value at the stage of rice-duck co-culture.The content of TN，TP，NH₄⁺-N，and NO₃^--N in the water of RDCI at the late stage of crayfish farming decreased by 11.1%，6.1%，14.4%，and 17.4%，compared with that of RCCC.The indexes mentioned above in RDCI at the stage of rice-duck coexistence increased from 81% to 135%，46% to 113%，55% to 715%，and 137% to 166%，respectively.The water quality of RDCI met the class Ⅲ standard during the initial crayfish farming，rice regreening，rice maturity，and overwintering stages，met the class Ⅳ standard during the later crayfish farming stage，and met the class Ⅴ standards during the rice-duck co-culture stage according to the comprehensive fuzzy evaluation of water quality based on the “Environmental Quality Standards for Surface Water” （GB 3838—2002）.It is indicated that RDCI reduces the surplus of water nutrients at the late stage of crayfish farming and replenishes the nutrient deficiency in the water at the stage of rice-duck co-cultivation to provide a better water environment compared with RCCC.