【Objective】The turnover of liable organic carbon (C) sources in soil is a key component of the cycle of soil carbon. Liable C sources (i.e. glucose), derived from C deposition in rhizosphere and other extraneous C inputs, are important sources of the C pool in the soil. Therefore, studying the turnover of liable C sources as affected by stoichiometric ratio of soil nutrients may help reveal mechanisms of the eco-stoichiometric regulation of the turnover of extraneous C in paddy soil. 【Method】In this study, an in-lab incubation experiment was conducted using ¹³C-glucose as extraneous organic C typical in paddy soil to explore quantitatively dynamics of decompositing mineralization and priming effect of glucose as affected by C/N/P/S stoichiometric ratio. 【Result】Results show that glucose was rapidly mineralized in the paddy soil so that 65.5% to 74.6% of the added glucose-C was mineralized after 60 d of incubation. The addition of nutrient elements not only increased glucose mineralization rate, but also raised the proportion of glucose-C available to soil microbes from 58% to 65%, thus accelerating glucose turnover rate in the soil. The amount of nutrient elements added was found significantly and positively related to both proportion of the microbe-available C pool in and mineralization rate (R ² = 0.63, p<0.05; R ²= 0.83, p< 0.05) of glucose C, which suggests that the addition of nutrient elements promoted the microbial utilization of extraneous C in the soil, and stoichiometric ratio of the nutrient elements regulated the dynamic of glucose mineralization. With the addition of glucose-C, the decomposition of the soil native organic matter was inhibited, and the cumulative negative priming effect was -370 to -570 mg kg^-1. The higher the amount of nutrient elements added, the stronger the negative priming effect observed, and the two were obviously in negative correlation (R ² = 0.66, p< 0.05), indicating that the soil microbes preferentially utilize the added glucose-C to sustain their growth. The supply of N, P and S reduced the dependence of microbes on nutrient elements in the soil native organic matter, and thereby slow down the decomposition of soil organic matter. 【Conclusion】Mineralization of liable C in paddy soil is affected by C/N/P/S stoichiometric ratio. The addition of a high ratio of nutrient elements promotes mineralization of liable C in paddy soil, inhibits decomposition of native soil organic matter, and intensify negative priming effect. All the findings in this study demonstrate that application of liable C and fertilizers to paddy soils could effectively inhibit decomposition of soil native organic matter, and stimulate accumulation of soil organic matter, thus building up soil fertility.