A liquid supply apparatus comprising: a compressed air supply source to compress air; a pressurizing tank (101, 102) to be supplied with the compressed air from the compressed air supply source and accumulate liquid pressurized by the compressed air; a feeder to feed the liquid accumulated in the pressurizing tank (101, 102) to a liquid flow path (203, 204, 205); a discharge head including an internal flow path through which the liquid fed from the liquid flow path (203, 204, 205) flows, the discharge head having a nozzle to discharge the liquid from the internal flow path; a mitigation device (131, 131-2, 131-3) installed on the liquid flow path (203, 204, 205) at a position downstream from the pressurizing tank (101, 102) and upstream from the discharge head, the mitigation device (131, 131-2, 131-3) to absorb a fluctuation in pressure of the liquid flowing through the liquid flow path (203, 204, 205), wherein the mitigation device is a piston pressing mechanism which includes an accumulator, a subtank, or a shock absorber; and a circulation path in which the feeder circulates the liquid in the liquid flow path (203, 204, 205) in an order of the pressurizing tank (101, 102), the mitigation device, the discharge head, and the pressurizing tank (101, 102), characterized in that the feeder is a pump that is installed on the liquid flow path (203, 204, 205) at a position downstream from the pressurizing tank (101, 102) and upstream from the mitigation device, to pressure-feed the liquid in the pressurizing tank (101, 102) toward the mitigation device and to the liquid flow path (203, 204, 205). a compressed air supply source to compress air; a pressurizing tank (101, 102) to be supplied with the compressed air from the compressed air supply source and accumulate liquid pressurized by the compressed air; a feeder to feed the liquid accumulated in the pressurizing tank (101, 102) to a liquid flow path (203, 204, 205); a discharge head including an internal flow path through which the liquid fed from the liquid flow path (203, 204, 205) flows, the discharge head having a nozzle to discharge the liquid from the internal flow path; a mitigation device (131, 131-2, 131-3) installed on the liquid flow path (203, 204, 205) at a position downstream from the pressurizing tank (101, 102) and upstream from the discharge head, the mitigation device (131, 131-2, 131-3) to absorb a fluctuation in pressure of the liquid flowing through the liquid flow path (203, 204, 205), wherein the mitigation device is a piston pressing mechanism which includes an accumulator, a subtank, or a shock absorber; and a circulation path in which the feeder circulates the liquid in the liquid flow path (203, 204, 205) in an order of the pressurizing tank (101, 102), the mitigation device, the discharge head, and the pressurizing tank (101, 102), characterized in that the feeder is a pump that is installed on the liquid flow path (203, 204, 205) at a position downstream from the pressurizing tank (101, 102) and upstream from the mitigation device, to pressure-feed the liquid in the pressurizing tank (101, 102) toward the mitigation device and to the liquid flow path (203, 204, 205).