The gutter cleaning device removes wet or dry debris in the gutter after being attached to a leaf blower, and is designed to be used while standing on the ground to reach gutters at the first, second and even third story levels without the need for a ladder. The gutter cleaning device includes a nozzle arranged at an angle to the gutter so that the flow of air drives debris in a direction away from the operator, and a fluid-driven agitation device powered simply by air pressure to mechanically stir up heavy debris in the gutter or to prevent the debris from clogging the nozzle. In addition, the gutter cleaning device includes a plough that protrudes forward relative to the nozzle and mechanically lifts compacted debris from the gutter to be blown away by the same flow of air that is used to drive the agitation device.