Provided are a light source module, a lighting device, and a system, which have uniform illuminance distribution, can obtain light having a large area, and are easy to assemble. The light module includes: a light source for emitting light; and a modulator disposed below the light source so as to modulate the emitted light into a line beam in the vertical direction. The light device includes a body, and a plurality of light source modules disposed on the lower side of the body so as to be arranged in an array in the horizontal direction, wherein the light source module includes: a support member provided in a first area of the lower side of the body; a light source provided in a second area of the lower side of the body so as to emit light in the downward direction; and the modulator provided on the lower side of the support member so as to modulate the emitted light into the line beam in the vertical direction.