To explore the impact of the changes of agricultural cropping-breeding mode(ACBM) on the water quantity and quality of rivers, Four Lakes Main Channel(FLMC) in the Jianghan Plain was taken as the research object. Based on observation data from 2010 to 2023, the trend of annual water quantity and quality changes was analyzed. Remote sensing images and statistical yearbook data were used to identify the interannual area change characteristics of different land utilization types, and the trends of nitrogen and phosphorus point source load were ascertained nearly 10 years, and redundancy analysis (RDA) and Correlation heat map were applied to explore the response of the main channel’s nitrogen and phosphorus concentration to the changes.The results indicate that: ①From 2010 to 2023, the concentration of total nitrogen and total phosphorus in FLMC , which the inter-annual was "increase and then decrease and then tend to be stable", the annual performance was "low in winter and spring, high in summer and autumn", and the spatial performance was "low and high in the middle of the inlet and outlet". The annual displacement of the total trunk canal is mainly concentrated in April to September, accounting for 65.7% of the whole year. ②In recent 10 years, the ACBM in the Sihu Basin has changed significantly, mainly showing that the dry land cultivation area has decreased by about 15%, the paddy field cultivation area has increased by about 19%, and the freshwater aquaculture area has increased by about 2% from 2010 to 2016, and decreased by more than 4% from 2016 to 2022. ③The variation characteristics of the total water quantity in the FLMC are not only affected by rainfall, but also related to the variation of rainfall runoff of different land use types in the basin, among which paddy field and dry land are the main influencing factors, and their contributions account for 366% and -236% of the total water quantity change, respectively. ④In recent 10 years, the changes of N and P concentration in the FLMC were positively correlated with the changes of N and P pollution load in the basin (79.7% interpretation, *p < 0.01), and the main factors that caused the changes of N and P pollution load in the basin were freshwater breeding and livestock breeding. In addition, the contribution of rice field cultivation to N and P loads increased from 6% to 26% in nearly 10 years, and the proportion of N and P loads gradually became prominent, and the risk of water environment pollution in the future cannot be ignored.