To investigate, using optical coherence tomography (OCT), whether retinal nerve fiber layer thickness (RNFLT) is affected in amblyopic eyes.Using OCT (Stratus OCT™ [Carl Zeiss, Dublin, CA]), the RNFLT was measured in 26 patients with persistent unilateral amblyopia and in 25 patients with recovered unilateral amblyopia. The RNFLT was compared between the affected and fellow eyes in patients with persistent amblyopia and in those with recovered amblyopia, and between the amblyopic eyes of patients with persistent amblyopia and the previously amblyopic eyes of patients with recovered amblyopia.In patients with persistent amblyopia and in those with recovered amblyopia, the affected eyes were significantly more hyperopic than the fellow eyes. The average (±standard deviation) RNFLT measured 105.5 ± 14.0 μm for the persistently amblyopic eyes; this value did not significantly differ from that of the fellow eyes (105.2 ± 13.0 μm) or the previously amblyopic eyes of recovered amblyopia (107.1 ± 11.7 μm). Also, logistic regression analysis adjusting for refraction showed no significant difference in the RNFLT between the persistently amblyopic eyes and the previously amblyopic eyes.Our results indicate that there is no significant change in the RNFLT in amblyopic eyes.