Conjunctival ultraviolet autofluorescence (CUVAF) area detected from UVAF photographs is a recently developed potential marker for past sun exposure, but its relationship with sun-related factors has not been fully investigated. The study included 339 healthy children ages 5 to 15 years in Melbourne, Australia. Data were collected by questionnaire and examination at school. CUVAF area was measured using a computer program and analyzed as a continuous and dichotomous outcome (any/none). Fifty-three children (15.6%) had detectable CUVAF, and the youngest age at which a child showed sun damage was 8 years. Compared with silicone skin cast score, there was good inter-grader agreement on CUVAF grading, with Cohen kappa 0.85 95% confidence interval (CI), 0.65-1.00 for total CUVAF area using both eye photographs. Perfect intra-grader agreement was achieved. Fairer pigmentation, including medium/fair skin color adjusted odds ratio (AOR), 3.42; 95% CI, 1.02-11.48 vs. dark/olive and blue/gray eye color (AOR, 4.07; 95% CI, 1.73-9.55 vs. brown) was associated with increased odds of CUVAF. Increasing lifetime sunburn number (e.g., AOR, 2.89; 95% CI, 1.14-7.35 and 4.29; 1.04-17.76 for sunburns 2 to 4 and ≥ 5 times, respectively, vs. no sunburns, trend = 0.004) and freckling by the end of last summer were associated with increased odds of CUVAF. CUVAF area can be an objective measure of past sun exposure in pediatric populations for future research. To our knowledge, this is the first pediatric study that evaluated associations of sun-related risk factors with CUVAF. .