Visual impairment due to glaucoma is irreversible; therefore, understanding its burden is important for implementing appropriate preventive measures. This study aimed to estimate the prevalence of visual impairment in patients with glaucoma. A hospital-based cross-sectional study was conducted on patients with glaucoma attending Hawassa University Comprehensive Specialized Hospital from May 1, 2022 to November 30, 2022. Visual acuity of 383 glaucomatous eyes from 275 patients was assessed using the Snellen illiterate acuity chart. Visual acuity at presentation and previous diagnoses were reviewed from the patient’s medical charts during the current checkup. Objective and subjective refractive measurements were performed for patients with a visual acuity of 6/18 or worse. Data collected using a validated structured questionnaire were cleaned, imported into Epinfo, and then exported to SPSS ver. 22. Descriptive and binary logistic regression analyses were conducted. Cofactors with a P<0.05 were considered statistically significant. Of the 383 eyes of 275 patients with glaucoma, approximately 38.12% (146/383) were visually impaired. Additionally, 35.28% (97/275) had visual impairment in at least one eye due to glaucoma, whereas 7.64% (21/275) were blind at initial presentation due to glaucoma. In the multivariable binary logistic regression analysis, age, duration of treatment, treatment adherence, distance from the hospital, laterality, and intraocular pressure at presentation were identified as factors significantly associated with visual impairment in patients with glaucoma. The burden of visual impairment in patients with glaucoma is high. Therefore, creating awareness, conducting glaucoma screening, and counseling patients about the importance of treatment adherence are important for reducing the burden of visual impairment due to glaucoma.