To determine whether cold knife conization (CKC) or loop electrosurgical excisional procedure (LEEP) is the better option for the treatment of cervical intraepithelial neoplasia (CIN) under specific circumstances. We retrospectively reviewed the medical records of patients who underwent CKC or LEEP for the treatment of CIN. The proportion of non-negative surgical margins between the two treatment groups was calculated based on their age, parity, previous mode of delivery, and grade of CIN. The Student's t-test and multivariate logistic regression analysis were used to find the better option for the treatment of CIN under the specific circumstances. A total of 118 patients were enrolled in the study. Between the two treatment groups, there was no significant difference in the overall proportion of non-negative surgical margins (P > 0.05). The grade of CIN, the previous mode of delivery, and parity did not affect the surgical margin status. The CKC treatment group had a significantly lower incidence of non-negative surgical margins than the LEEP treatment group (14.3% vs. 52.6%, respectively; P < 0.05) in the patients >45 years of age. Based on multivariate analyses, LEEP was identified as a significant risk factor for non-negative surgical margins in the patients >45 years of age. Of the 11 patients with non-negative surgical margins who underwent a secondary procedure within 6 months of the initial CKC or LEEP, five patients (45.5%) had residual CIN II and III. In patients >45 years of age, CKC is the preferred treatment for CIN.