Objective To detecte the pathogenetic mechanism of cortical deficit in persons with strabismic amblyopia by blood oxygenation level dependent-functional magnetic resonance imaging (BOLD-fMRI). Methods The data of BOLD-fMRI of occipital visual cortex in 11 persons with strabismic amblyopia and 8 healthy ones were collected by 1.5T MRI system. The results of binocular pixel exponent in strabismic amblyopia group was compared with that in the normal group and the result of and average activation of cortical neuron in strabismic amblyopia group was analyzed. Results The binocular pixel exponent was lower in the strabismic amblyopia group (14.13%?4.55%) than that in the normal group(47.82%?5.34%) ( P