Abstract: Background and Objective: Stalk of Lentinus edodes, which often discarded in large amounts after Lentinus edodes process is a kind of material that is rich in dietary fiber. The objective of study was to obtain a suitable way to extract Soluble Dietary Fiber (SDF) from the stalks of Lentinus edodes and provide theoretical basis for further processing of it. Methodology: According to single-factor and response surface methodologies, suitable conditions for extracting SDF were determined through enzymatic hydrolysis based on extraction yield of water-SDF and one-way-analysis of variance (ANOVA) followed by Least Significant Difference test (LSD) and Duncan’s multiple range test (Duncan) at p<0.05 were used to verify significant differences in evaluated parameters. Results: The optimal conditions for the SDF extraction rate are 52°C extraction temperature, 87 U g–1 enzyme concentration, 100 mesh number and 50 min extraction duration. On this condition, the SDF extraction rate is 14.33%. Water holding capacity and swelling property of SDF from stalks of Lentinus edodes measured 10 g/g and 0.93 mL g–1, respectively. Conclusion: It is concluded that stalks of Lentinus edodes serve as good sources of SDF. Reliable and feasible optimization of SDF extraction from stalks of Lentinus edodes can be achieved through response surface method.