To assess and compare the impacts of dental caries on quality of life among visually impaired and sighted 10- to 19-year-old adolescents before and after treatment in Lagos State, Nigeria. A cross-sectional study of institutionalized sighted and visually impaired 10- to 19-year-old adolescents was carried out using interviewer-administered Oral Health Related Quality of Life questionnaire based on Child Oral Impact on Daily Performance (Child-OIDP) questionnaire. Frequencies of impact and mean impact scores were determined and compared between the two groups using chi-square test. SPSS IBM version 20 was used for the analysis. The level of significance was placed at P<0.05. The mean impact scores on quality of life among sighted and visually impaired adolescents were 14.45 ± 17.00 and 12.61 ± 17.83, respectively before treatment (P=0.55) as well as 0.54 ± 1.81 and 2.02 ± 6.86 respectively after treatment (P=0.10). The visually impaired adolescents suffered similar burden of impact of dental caries as their sighted peers. The greatest impact was on eating and cleaning the teeth. Impact was greatly reduced following treatment. There is need for oral health promotion and early detection of dental caries among institutionalized visually impaired and sighted adolescents in order to prevent complications of dental caries.