Abstract: An apparatus for supplying fluid of preset quantity comprises a fluid supplying pump provided in a fluid supplying pipe arrangement, a motor for driving the fluid supplying pump, meter for metering the fluid flowing in the fluid supplying pipe arrangement, and a control circuit for detecting that supplied quantity of fluid measured by the meter has reached a quantity smaller than a preset fluid supplying quantity by an estimated oversupply quantity of fluid, and stopping the motor from being driven. The estimated oversupply quantity of fluid is set to a quantity equal to a quantity of fluid supplied by the fluid supplying pump after the motor is stopped from being driven and rotates due to inertia.