BACKGROUND Combined phacovitrectomy is gaining popularity due to efficiency and immediate visual improvement. However, concerns regarding erroneous intraocular lens (IOL) calculation in combination surgery are increasing, such as myopic shift owing to a thick macula and consequent underestimation of the axial length. Therefore, this study aimed to compare the refractive outcomes of combined phacovitrectomy in patients with highly myopic and non-highly myopic eyes. METHODS A retrospective chart review was performed on patients who received combined phacoemulsification, intraocular lens implantation, and small gauge pars plana vitrectomy for cataract and macular pathologies in highly myopic and non-highly myopic eyes. Pre- and postoperative evaluation and ocular parameters were recorded, and analyses were performed using the Student's t test and regression analysis. RESULTS A total of 133 patients with macular pathologies, including myopic tractional maculopathy, macular hole, and epiretinal membrane, were enrolled. SRK II or SRK/T models were used for calculating IOL. The mean absolute error of refraction change was 0.65 D; 83.5% of patients were within 1-D error, 57.9% within 0.5-D error, and 35.3% within 0.25-D error, with SRK/T showing better precision and yielding more myopic shift. Furthermore, the predictive accuracy of SRK II or SRK/T was better in patients with non-highly myopic eyes. Moreover, Barrett's universal II formula was not superior to SRK II or SRK/T in the prediction of postoperative refractive error (p = 0.48). CONCLUSIONS Refractive outcomes were satisfactory in the cohort of patients with highly myopic eyes. The combined implementation of SRK II and SRK/T was not inferior to Barrett's universal II formula in predicting satisfactory refractive outcomes. Combination surgery can be an option for patients with both cataract and macular pathologies.