【Objective】This study aimed to evaluate the impact of various phosphorus (P) fertilizer application rates and irrigation methods on rice yield, P uptake, P loss, and P balance in the Taihu Lake Basin. The goal was to optimize nutrient management and mitigate non-point source pollution by assessing the effects of different P levels and water management practices on rice paddies. 【Method】The research applied a two-year field experiment with three P application rates (P2O5 0, 45, and 90 kg·hm-2) and three irrigation strategies: continuous flooding, mild dryness, and severe dryness. Soil and rice samples were collected at harvest. Soil P fractions were analyzed using sequential extraction, and rice yield and P uptake were measured from grain and straw. Runoff and leachate samples were obtained to assess P loss. 【Result】Compared to the control treatment (no phosphate fertilizer), applying P fertilizer increased rice yield by 2.20% to 11.5%. The P2O5 90 kg·hm-2 treatment reduced P agronomic and P use efficiencies by an average of 34.9% and 29.4%, respectively, compared to the application of P2O5 45 kg·hm-2. P application significantly increased the soil Olsen-P and available P fractions (the sum of Resin-P, NaHCO3-Pi, and NaOH-Pi) by 19.1%~62.4% and 36.5%~101%, respectively, while also enhancing P loss from paddy fields by 79.1% to 292%, compared to the control. In addition, the mild and severe dryness strategies significantly reduced P loss, with average decreases of 27.0% and 35.6%, respectively, particularly in runoff, where reductions were 31.5% and 41.3%, compared to flooding. The P2O5 90 kg·hm-2 treatment maintained a P balance for the rice season, while the application of P2O5 45 kg·hm-2 was sufficient to meet rice demands due to the high availability of soil P and Olsen-P higher than 20 mg·kg-1. Structural equation modeling indicated that Olsen-P and NaOH-Pi were the main influencing factors for rice yield, while Resin-P was the main influencing factor of P loss. 【Conclusion】Moderate P fertilization at P2O5 45 kg·hm-2 effectively increased rice yield with minimal P loss. Mild dryness irrigation and appropriate P application based on crop P requirements and soil P levels are vital for maximizing crop yields while minimizing P loss. The findings provide a scientific basis for nutrient management in paddy fields and the control of non-point source pollution in the Taihu Lake Basin.