AIM: To study the perception of first-order grating acuity and second-order spatial contrast sensitivity in patients with monocular anisometropia amblyopia.METHODS:A total of 715 children(715 eyes)diagnosed as monocular anisometropia amblyopia in our hospital from January 2018 to December 2022 were collected as amblyopia group, and 745 children(745 eyes)with normal corrected visual acuity were collected. The best corrected visual acuity(BCVA), first-order grating acuity and/or second-order spatial contrast sensitivity were measured, repectively. The perception ability of amblyopia patients to first-order grating acuity and second-order spatial contrast sensitivity were analyzed.RESULTS:There were significant differences between amblyopia group and normal control group in the perception of first-order grating acuity(11.58±6.10 vs. 20.27±3.47, P<0.001)and second-order spatial contrast sensitivity(0.33±0.16 vs 0.12±0.04, P<0.001). And there were significant differences between mild-to-moderate amblyopia and severe amblyopia patients in first-order grating acuity(12.10±6.23 vs. 8.13±3.70, P<0.001)and second-order spatial contrast sensitivity(0.32±0.16 vs. 0.37±0.17, P<0.05).CONCLUSION: The first-order and second-order visual pathway of the cerebral cortex in children with monocular anisometropia amblyopia have different degrees of damage. The injury of severe amblyopia is more serious than that of mild-to-moderate amblyopia.