The invention provides an optical write line head comprising multiple rows of light emitter devices lined up corresponding to the respective positive lenses located in array form, wherein even with a fluctuation of its write plane in an optical axis direction, there is none of variations resulting from displacements of light emitting dots. A plurality of light emitter blocks 4, each including at least one row of light emitter devices lined up in a main scan direction, are located at a spacing in the main scan direction to define a light emitter array 1. On the exit side of the light emitter array 1, a lens array 6 comprising one positive lens system 5 in alignment with each light emitter block 4 is located parallel with the light emitter array 1, and a write plane 41 is located parallel on the imaging side of the lens array 6. A stop plate 30 forming an aperture stop 31 is located near a light-gathering position at which parallel light incident from the write plane side on each positive lens system comes together.