Abstract: 【Objective】The study was to reveal the effects of combined application of organic and inorganic fertilizers on main agronomic traits and yield of rice, soil environment and soil fertility, and explore the proper proportion of pure nitrogen in the combined application of organic and inorganic fertilizers.【Method】Field trials were conducted in southern double-cropping rice fields, and a randomized block design with six treatments, including 100% NPK chemical fertilizer（T1）, 80% NPK chemical fertilizer + 20% organic fertilizer（T2）, 60% NPK chemical fertilizer + 40% organic fertilizer（T3）, 20% NPK chemical fertilizer + 80% organic fertilizer（T4）, 100% organic fertilizer（T5）and no fertilization（CK, T6）, was conducted to compare the differences in rice yield, effective panicle number, rice straw dry weight, and changes in soil physical and chemical properties.【Result】The application of 20%-40% pure nitrogen which came from organic fertilizer could increase effective panicle number of rice and soil organic matter content of 6.9%-31.5%, reduce rice straw dry weight of 6.1%-6.9%, show higher agronomic efficiency of nitrogen fertilizer and no obvious change in soil pH.【Conclusion】The 【Objective】The study was to reveal the effects of combined application of organic and inorganic fertilizers on main agronomic traits and yield of rice, soil environment and soil fertility, and explore the proper proportion of pure nitrogen in the combined application of organic and inorganic fertilizers.【Method】Field trials were conducted in southern double-cropping rice fields, and a randomized block design with six treatments, including 100% NPK chemical fertilizer（T1）, 80% NPK chemical fertilizer + 20% organic fertilizer（T2）, 60% NPK chemical fertilizer + 40% organic fertilizer（T3）, 20% NPK chemical fertilizer + 80% organic fertilizer（T4）, 100% organic fertilizer（T5）and no fertilization（CK, T6）, was conducted to compare the differences in rice yield, effective panicle number, rice straw dry weight, and changes in soil physical and chemical properties.【Result】The application of 20%-40% pure nitrogen which came from organic fertilizer could increase effective panicle number of rice and soil organic matter content of 6.9%-31.5%, reduce rice straw dry weight of 6.1%-6.9%, show higher agronomic efficiency of nitrogen fertilizer and no obvious change in soil pH.【Conclusion】The combined application of organic and inorganic fertilizers is beneficial to reduce the application of chemical fertilizers. 20%- 40% pure nitrogen provided by the combined application of organic and inorganic fertilizers has the best overall effect on increasing the rice yield and reducing the negative environmental effects of nitrogen fertilizer. The fertilizer and ecological 【Objective】The study was to reveal the effects of combined application of organic and inorganic fertilizers on main agronomic traits and yield of rice, soil environment and soil fertility, and explore the proper proportion of pure nitrogen in the combined application of organic and inorganic fertilizers.【Method】Field trials were conducted in southern double-cropping rice fields, and a randomized block design with six treatments, including 100% NPK chemical fertilizer（T1）, 80% NPK chemical fertilizer + 20% organic fertilizer（T2）, 60% NPK chemical fertilizer + 40% organic fertilizer（T3）, 20% NPK chemical fertilizer + 80% organic fertilizer（T4）, 100% organic fertilizer（T5）and no fertilization（CK, T6）, was conducted to compare the differences in rice yield, effective panicle number, rice straw dry weight, and changes in soil physical and chemical properties.【Result】The application of 20%-40% pure nitrogen which came from organic fertilizer could increase effective panicle number of rice and soil organic matter content of 6.9%-31.5%, reduce rice straw dry weight of 6.1%-6.9%, show higher agronomic efficiency of nitrogen fertilizer and no obvious change in soil pH.【Conclusion】The combined application of organic and inorganic fertilizers is beneficial to reduce the application of chemical fertilizers. 20%- 40% pure nitrogen provided by the combined application of organic and inorganic fertilizers has the best overall effect on increasing the rice yield and reducing the negative environmental effects of nitrogen fertilizer. The fertilizer and ecological 【Objective】The study was to reveal the effects of combined application of organic and inorganic fertilizers on main agronomic traits and yield of rice, soil environment and soil fertility, and explore the proper proportion of pure nitrogen in the combined application of organic and inorganic fertilizers.【Method】Field trials were conducted in southern double-cropping rice fields, and a randomized block design with six treatments, including 100% NPK chemical fertilizer（T1）, 80% NPK chemical fertilizer + 20% organic fertilizer（T2）, 60% NPK chemical fertilizer + 40% organic fertilizer（T3）, 20% NPK chemical fertilizer + 80% organic fertilizer（T4）, 100% organic fertilizer（T5）and no fertilization（CK, T6）, was conducted to compare the differences in rice yield, effective panicle number, rice straw dry weight, and changes in soil physical and chemical properties.【Result】The application of 20%-40% pure nitrogen which came from organic fertilizer could increase effective panicle number of rice and soil organic matter content of 6.9%-31.5%, reduce rice straw dry weight of 6.1%-6.9%, show higher agronomic efficiency of nitrogen fertilizer and no obvious change in soil pH.【Conclusion】The combined application of organic and inorganic fertilizers is beneficial to reduce the application of chemical fertilizers. 20%- 40% pure nitrogen provided by the combined application of organic and inorganic fertilizers has the best overall effect on increasing the rice yield and reducing the negative environmental effects of nitrogen fertilizer. The fertilizer and ecological benefits are significant.