AIM: To evaluate the therapeutic effect of combined phacovitrectomy with membrane peeling and intraocular lens (IOL) implantation in patients with severe idiopathic epiretinal membrane (iERM) and concurrent cataract. METHODS: A total of 34 eyes from 34 patients who underwent phacovitrectomy and epiretinal membrane (ERM) peeling at the First Affiliated Hospital of Zhejiang University between 2015 and 2017. The best-corrected visual acuity (BCVA) and central foveal thickness (CFT) were measured preoperatively and at 1, 3, 6mo and 1y postoperatively. Temporal changes and bivariate correlations of these parameters were analyzed. RESULTS: Mean logMAR BCVA improved and CFT decreased significantly (P<0.001) until 6mo after surgery. Correlation analysis revealed a positive correlation between preoperative and postoperative logMAR BCVA (r=0.716, P<0.001 at 1mo, r=0.417, P=0.014 at 3mo, r=0.359, P=0.037 at 6mo, and r=0.369, P=0.032 at 12mo post-op respectively), but preoperative CFT was neither associated with postoperative CFT nor with postoperative logMAR BCVA. There was a positive correlation between CFT and logMAR BCVA at 1mo (r=0.346, P=0.045), 6mo (r=0.347, P=0.045), and 12mo (r=0.342, P=0.048) post-operatively. The intra- and postoperative complications were relatively mild, and the incidences were generally low. CONCLUSION: For severe iERM patients with significant visual symptoms, combined phacovitrectomy with membrane peeling and IOL implantation is safe and effective in improving BCVA and decreasing CFT. Early surgery in selected patients may help preserving better visual function.