This study evaluated the reproducibility of the Teller Acuity Cards (TAC) test, its correlation with the optotype test, and its usefulness for detecting amblyopia in preliterate children. We retrospectively reviewed the medical records of 64 children who had undergone the TAC test more than once and were later followed up with the optotype test. The mean corrected visual acuities (logMAR) of the first and last TAC tests were 0.86 (mean 19.9 months) and 0.69 (27.7 months), respectively. The first optotype acuity was 0.18 (33.7 months). The first TAC acuity result was positively correlated with the age of the child, but it was not statistically significant (r = -0.077, p > 0.05). The first and last TAC test acuities were significantly correlated (r = 0.382, p < 0.01). There was a significant but small correlation between the final TAC and the first optotype acuities (r = 0.193, p < 0.05). Interocular differences in visual acuity were significantly correlated between the last TAC and first optotype tests (r = 0.395, p < 0.05). TAC acuity might be a valid predictor of optotype acuity later on although it was underestimated compared to that in the optotype test. The TAC test can be used to detect unilateral amblyopia in preliterate children.