Objective To investigate the applicability of the eysphonia severity index (DSI) in evaluating effects of surgery between before and after groups of vocal polyp patients.Methods Analyses of measurement data pre and pro-surgery of 70 vocal polyp patients and 35 no voice disorders volunteers(control group).The voice quality was measured subjectively with the voice handicap index(VHI),the GRBAS and fiber electronic laryngoscopy.Measures of maximum phonation time (MPT),shimmer and jitter were obtained for each subject by using DiVAS 2.30 (XION,Germany).The DiVAS 2.30 had spotanenously calculate the scores of DSI.Using SPSS 17.0 to find the differences of DSI scores among the three groups by one-way ANOVA variance analysis.And finding out of the correlation with DSI scores and VHI scores,GRBAS,MPT,jitter and shimmer.Results DSI improved significantly after surgery in the vocal polyps group (mean difference DSI-2.92 and 1.87,respectively) and also in the control group (mean difference DSI-2.92 and 2.30,respectively).However,no significant difference between the control group and the after surgery group.By using Pearson correlation analysis,this study observed a strong correlation between the DSI scores and the VHI scores,the values of GRBAS,shimmer (P ＜ 0.01).Conclusions DSI is an effective and high accuracy multi-parameter system for evaluation of vocal cord polyp patients as an independent assessment of dysphonia.DSI also can be used in evaluation of the effects of the vocal polyps surgery.