The invention discloses a nuclear magnetic resonance core permeability imaging method. The method comprises the following steps: soaking tested core samples by corresponding needed time, measuring thesoaked samples to obtain T2 relaxation time after oil and water phase separation, and performing similar treatment on saturated samples; performing arithmetic processing on the amplitude of various points of the relaxation time spectrum of the soaked samples and the relaxation time spectrum of the saturated samples so as to obtain oil saturation of the samples; and converting magnetic resonance relaxation time distribution into pore radius distribution by taking the length as the unit, thereby obtaining the rock pore radius distribution.