The dilemma in treating cervical high-grade squamous intraepithelial lesion (HSIL) is how to achieve complete excision to minimize the risk of cervical cancer while sparing the anatomy of the cervix and its ability to function during pregnancy. The optimal management for positive margins after excisional treatment is still controversial. This study was conducted to determine the clinical and histologic predictors of residual/recurrent HSIL and assess the outcome of women with positive margin. This retrospective cohort study included 386 women who had excisional treatment for HSIL during 1st January 2012 to 31st December 2015 in a university-affiliated hospital. Overall, 212 (54.9%) women had negative margins and 155 (40.2%) had positive margins. The cumulative rate of residual/recurrent HSIL at 2 and 5 years was 15.7% and 16.8% respectively in positive margins and 1.8% and 5.0% respectively in negative margins (p < 0.001). Of women who had residual/recurrent HSIL, significantly more women had positive margins compared to negative margins (74.1% vs 25.9%, p = 0.001). Positive margin was significantly associated with higher rate of subsequent abnormal cervical smear (48.2% vs 28.9%, p < 0.001), requiring further colposcopy (32.1% vs 14.4%, p < 0.001) and further treatment for SIL (7.5% vs 4.8%, p < 0.001) compared to negative margin. Most women (85%) with positive margin went without residual/recurrent HSIL, of which the option of close surveillance with cytology is reasonable. Repeat excision may be considered in selected women with positive margin, endocervical glandular involvement and those who are older or unable to comply with follow-up.