Abstract: To develop the resource utilization of peony husk， microwave-assisted extraction of water-soluble dietary fiber（SDF） from peony husk was used in this study. Single-factor experiments were performed by selecting the citric acid concentration， material/liquid ratio，microwave power，and microwave time. Based on the single-factor experiment， the response surface methodology was utilized to optimize the extraction process. The three variables of material/liquid ratio （A），microwave power （B），and microwave time（C）were selected as the dependent variables that had a large effect on the SDF extraction rate，and the SDF extraction rate was taken as the response value （Y）. Design-Expert8.6.0 was used to design three factors and three levels，and a response surface test was performed to establish the regression equation between each dependent variable and response value. The regression equation fitted well，and the effect on the SDF yield was material/liquid ratio > microwave power > microwave time. The optimal process conditions for microwave-assisted extraction of SDF were as follows：material/liquid ratio was 1∶26. 19，microwave power was medium fire，and the microwave time was 63. 6 s. Under such conditions，the SDF extraction rate could reach 45. 99%. In this study，the SDF microwave extraction technology of peony husk was established， which had a guiding significance for the in-depth development and utilization of peony husk resources.

Key words: peony husk, water-soluble dietary fiber, microwave-assisted extraction, response surface analysis