A robot cleaner may include a main body, a light irradiation unit irradiating light towards a region in front of the main body, an image sensor including a plurality of horizontal lines sequentially exposed to form an image, an image processing unit constructing frames by synchronizing signals output from the horizontal lines, such that, after construction of any one frame, the image processing unit does not construct one or more frames by ignoring signals output from the horizontal lines, and then constructs a next frame, and a controller controlling the light irradiation unit to irradiate light while the horizontal lines are exposed to construct the one frame, such that the light irradiation unit stops irradiation of light between before exposure of all the horizontal lines to construct the frame is completed and one point of time while the image processing unit ignores signals output from the horizontal lines.