The present disclosure relates to an easily foldable soft box, a lighting device that softens and spread light over a wide area, that comes with a diffuser (diffusing cover) that can fold easily with one touch, making it easy to collapse (and expand) the device. The easily foldable soft box comprises: a speed ring having the shape of a ring that allows a light-producing device to be mounted at an opening in the center, whose front part is configured to fold in half or unfold; a plurality of ribs attached to the front part, that are arranged in a radiating pattern around the speed ring when the front part is unfolded, and that are gathered together as the ribs arranged within one range overlap the ribs arranged within another range when the front part is folded in half; and a diffuser that unfolds like an umbrella to diffuse light produced by the light-producing device when the ribs are arranged in a radiating pattern, and that is folded by the ribs when the front part is folded.