Purpose: To evaluate the effectiveness and clinical significance of pattern visual evoked potential (P-VEP) parameters on visual acuity in amblyopic patients under occlusion therapy. Methods: A total of 34 consecutive children with anisometropic amblyopia were included in this study. All patients underwent a full initial ophthalmologic and orthoptic evaluation. P-VEP test was performed in all cases and binocular vision was tested and recorded with Worth's four-dot test and Bagolini striated glasses at each visit. Part-time occlusion therapy was performed by using adhesive patches. Results: The mean (+/- SEM) cycloplegic refractive error was + 5.6 +/- 0.6 diopters (D) in the amblyopic eyes and + 1.8 +/- 0.2 D in the normal eye. The mean levels of best-corrected visual acuity were statistically differed between each measurement for occlusion therapy (for each, p < 0.05). The ratio of the patients with binocular vision increased after 6 months occlusion therapy and the difference was statistically significant (p < 0.05). In addition, P100 amplitude improved at each visit and the difference was significant when compared with baseline values (for each, p < 0.05). Conclusions: P100 amplitude of the P-VEP test parallels the improvement in subjective visual acuity in amblyopic eyes under occlusion therapy. Therefore, this test may be useful in monitoring the visual acuity in the preverbal or non-verbal patched patients.