Embodiments of the present disclosure provide a MEMS light valve, which includes: a fixed grating partitioned into first regions and second regions, which are arranged alternately, wherein the fixed grating comprises reflective units configured within the first regions for reflecting at least part of incident light and the second regions do not reflect light; and a movable grating located at a side of the fixed grating to which outside light is incident and movable in a plane where the movable grating is located, wherein the movable grating is capable of block part or all of the reflective units during moving. The embodiments of the present disclosure are adopted to manufacture of a MEMS light valve and a display device including the MEMS light valve.