IMPORTANCE: Given the limitations in health care resources, quality-of-life measures for interventions have gained importance. OBJECTIVE: To determine whether vision-related quality-of-life outcomes were different between the natamycin and voriconazole treatment arms in the Mycotic Ulcer Treatment Trial I, as measured by an Indian Vision Function Questionnaire. DESIGN, SETTING, AND PARTICIPANTS: Secondary analysis (performed October 11-25, 2014) of a double-masked, multicenter, randomized, active comparator-controlled, clinical trial at multiple locations of the Aravind Eye Care System in South India that enrolled patients with culture- or smear-positive filamentous fungal corneal ulcers who had a baseline visual acuity of 20/40 to 20/400 (logMAR of 0.3-1.3). INTERVENTIONS: Study participants were randomly assigned to topical voriconazole, 1%, or topical natamycin, 5%. MAIN OUTCOMES AND MEASURES: Subscale score on the Indian Vision Function Questionnaire from each of the 4 subscales (mobility, activity limitation, psychosocial impact, and visual function) at 3 months. RESULTS: A total of 323 patients were enrolled in the trial, and 292 (90.4%) completed the Indian Vision Function Questionnaire at 3 months. The majority of study participants had subscale scores consistent with excellent function. After adjusting for baseline visual acuity and organism, we found that study participants in the natamycin-treated group scored, on average, 4.3 points (95%CI, 0.1-8.5) higher than study participants in the voriconazoletreated group (P =.046). In subgroup analyses looking at ulcers caused by Fusarium species and adjusting for baseline best spectacle-corrected visual acuity, the natamycin-treated group scored 8.4 points (95%CI, 1.9-14.9) higher than the voriconazole-treated group (P =.01). Differences in quality of life were not detected for patients with Aspergillus or other non-Fusarium species as the causative organism (1.5 points [95%CI, -3.9 to 6.9]; P =.52). CONCLUSIONS AND RELEVANCE: We found evidence of improvement in vision-related quality of life among patients with fungal ulcers who were randomly assigned to natamycin compared with those randomly assigned to voriconazole, and especially among patients with Fusarium species as the causative organism. Incorporation of quality-of-life measures in clinical trials is important to fully evaluate the effect of the studied interventions.