The study analyzed phosphorus distribution in the Yangtze River to understand pollution levels. Results showed higher total phosphorus concentrations downstream, with the left bank having more than the right bank. Total dissolved phosphorus levels were also higher downstream. Particulate phosphorus was the main contributor to total phosphorus, decreasing along the river. Soluble orthophosphate levels increased downstream and accounted for over 70% of total dissolved phosphorus. Overall, phosphorus levels were low in the middle and lower reaches of the Yangtze River, indicating good water quality.