The effect of combined application of organic and inorganic fertilizers on soil fertility properties and rice growth was researched by dynamic sampling and analysis in field experiment to reduce harm of the obstacle characteristics in cold paddy soil such as low temperature,flooding,bad structure and low soil available nutrient.The results showed that compared with compound fertilizer,in treatment of combination of organic(40%N) and inorganic fertilization soil FeP and CaP contents were increased by 11% and 17% respectively;in treatment of combination of organic(60%N) and inorganic fertilization soil AlP contents was increased by 44%,and the percentage of AlP,FeP and CaP were increased,the percentage of OP was reduced,the transformation of insoluble phosphate to the soluble phosphorus was promoted,content of soil available phosphorus was increased,the contribution of loosely combined humus to total humus was increased by 1.9%,the contribution of tightly combined humus to total humus was reduced by 4.6%,the active organic matter contents and cation exchange capacity were increased by 14% and 11% respectively.Fungus and actinomycetes contents were increased by 33% and 28% respectively in treatment of combination of organic(40%N) and inorganic fertilization.Bacterium content and microorganism activity in treatment of combination of organic(60%N) and inorganic fertilization were increased by 160% and 19% respectively,and the absorption of phosphorus and potassium by rice were increased by 5% and 111% respectively.The early rice yield and late rice yield in combination of organic(40%N) and inorganic fertilization were increased by 8% and 42%,while in combination of organic(60%N) and inorganic fertilization they were increased by 6% and by 31%,respectively.Effect of organic and inorganic balance fertilization was efficient in improving cold spring paddy soil fertility and increasing rice yield.