Abstract: In order to solve the problem of rice root slow growth and root premature decay in late stage. On the basis of the open ditch drainage, experiment was conducted to study the effects of different soil amendments (self-developed desulphurization ash amendment, biomass charcoal, lime, silico-calcium fertilizer, humic acid) on root activity, biomass, root shoot ratio, the flux of N, P, K in bleeding sap and rice yield in south typical cold spring paddy soils. The results showed that, treatments with amendments, except for lime, significantly increased the intensity of bleeding sap, root shoot ratio, biomass and enhanced the flux of N, P, K in bleeding sap. Treatments with desulphurization amendment and biomass charcoal increased the intensity of bleeding sap most. Compared with CK, the flux of P in bleeding sap increased by 29.60% and 19.70% respectively during filling stage. The root shoot ratio of treatment with desulphurization ash increased by 31.6% compared to CK at mid-tillering stage. Different soil amendments could improve rice yield of cold waterlogged paddy field. Besides, the effect of yield increase would increase with the application of amendments. To sum up, amendments of desulphurization ash amendment and biomass charcoal could be the optimal choice for cold waterlogged paddy field.