A head cleaning device for cleaning liquid ejection surfaces of ink jet heads, comprising: cleaning liquid holding means that includes a cleaning liquid holding surface having an inclination corresponding to an inclination of a liquid ejection surface of an ink jet head inclined with respect to a horizontal plane, cleanable with the head cleaning device, and has a structure in which the cleaning liquid holding surface and the liquid ejection surface are disposed so as to have a gap therebetween, in a state where the cleaning liquid holding surface and the liquid ejection surface face each other; relative movement means (284, 286A, 289) capable of relatively moving the inkjet head with respect to the cleaning liquid holding means, in a state where the liquid ejection surface of the ink jet head and the cleaning liquid holding surface face each other, and the gap between the liquid ejection surface and the cleaning liquid holding surface is maintained constant; and cleaning liquid supply means; characterized in that the cleaning liquid supply means includes a cleaning liquid supply port for supplying cleaning liquid from the upper portion of an inclination of the cleaning liquid holding surface to the cleaning liquid holding surface, in a state where the cleaning liquid holding surface and the liquid ejection surface face each other, wherein the cleaning liquid supply means has a structure in which the outer edge of the cleaning liquid supply port on the downstream side in a movement direction, in a state where the ink jet head is moved with respect to the cleaning liquid holding means being fixed, is disposed further to the upstream side than the center in the movement direction of the cleaning liquid holding surface. cleaning liquid holding means that includes a cleaning liquid holding surface having an inclination corresponding to an inclination of a liquid ejection surface of an ink jet head inclined with respect to a horizontal plane, cleanable with the head cleaning device, and has a structure in which the cleaning liquid holding surface and the liquid ejection surface are disposed so as to have a gap therebetween, in a state where the cleaning liquid holding surface and the liquid ejection surface face each other; relative movement means (284, 286A, 289) capable of relatively moving the inkjet head with respect to the cleaning liquid holding means, in a state where the liquid ejection surface of the ink jet head and the cleaning liquid holding surface face each other, and the gap between the liquid ejection surface and the cleaning liquid holding surface is maintained constant; and cleaning liquid supply means; characterized in that the cleaning liquid supply means includes a cleaning liquid supply port for supplying cleaning liquid from the upper portion of an inclination of the cleaning liquid holding surface to the cleaning liquid holding surface, in a state where the cleaning liquid holding surface and the liquid ejection surface face each other, wherein the cleaning liquid supply means has a structure in which the outer edge of the cleaning liquid supply port on the downstream side in a movement direction, in a state where the ink jet head is moved with respect to the cleaning liquid holding means being fixed, is disposed further to the upstream side than the center in the movement direction of the cleaning liquid holding surface.