Many subjects, especially highly educated subjects, are increasingly exposed to computer use. This exposure might represent an explanation for the growing rates of myopia.We assessed 17,217 Spanish university graduates from the SUN project, an open-recruitment cohort. Their mean age was 38.5 years (SD 12.1), and their mean time of exposure to computers was 14.3h/week (SD 14.6). We estimated multivariable-adjusted odds ratios (OR) for the risk of myopia development and/or progression (≥0.5 diopters) according to baseline exposure to computer and to changes in exposure.The age and sex-adjusted OR comparing >40 h/week of exposure versus<10h/week was 1.34 (95% confidence interval (CI): 1.12-1.60). This association remained essentially unchanged after additional adjustments. Comparing participants who increased their exposure to computers, versus those with no change, the age and sex-adjusted OR was 1.49 (1.34-1.66). This result was unchanged after additional adjustments.To our knowledge this is the first large longitudinal assessment in young adults, showing that exposure to computer use is associated with myopia development or progression in a cohort of Spanish university graduates. Further studies are needed to confirm these epidemiological findings.