A washing machine comprising: a tub accommodating wash water; a drum rotatably arranged in the tub and accommodating laundry; a drive unit for rotating the drum; a water supply unit for adjusting an inflow of the wash water from an external water source; a pump for pumping the wash water in the tub such that the wash water is circulated in the tub or is discharged to the outside; and a control unit for controlling the drive unit, the water supply unit, and the pump, wherein the control unit performs, a laundry amount detection step of detecting an amount of laundry, a wash water supply step of performing preliminary washing before a washing step, by mixing wash water supplied from the external water source with detergent, supplying the wash water into the tub, and wetting laundry in the wash water mixed with the detergent, and the washing step which is a step of repeatedly tumbling laundry by rotating the drum at various speeds or in various directions, a circulation nozzle for spraying the wash water circulated by the pump into the drum, characterized in that: in the laundry amount detection step, the control unit drives the drive unit and detects an amount of the laundry accommodated in the drum so as to set a target water level, which is a target amount of wash water which is supplied into the tub after the completion of the wash water supply step, wherein in the wash water supply step, the control unit controls the water supply unit to supply the wash water into the tub such that a level of the wash water is lower than the target water level, drives the drive unit to accelerate the drum at a rotational speed in a state in which the laundry is attached to the drum and drives the pump when the drum is accelerated, so as to spray the wash water, circulated through the circulation nozzle, into the drum, and controls the water supply unit to supply the wash water into the tub until the target water level. a tub accommodating wash water; a drum rotatably arranged in the tub and accommodating laundry; a drive unit for rotating the drum; a water supply unit for adjusting an inflow of the wash water from an external water source; a pump for pumping the wash water in the tub such that the wash water is circulated in the tub or is discharged to the outside; and a control unit for controlling the drive unit, the water supply unit, and the pump, wherein the control unit performs, a laundry amount detection step of detecting an amount of laundry, a wash water supply step of performing preliminary washing before a washing step, by mixing wash water supplied from the external water source with detergent, supplying the wash water into the tub, and wetting laundry in the wash water mixed with the detergent, and the washing step which is a step of repeatedly tumbling laundry by rotating the drum at various speeds or in various directions, a circulation nozzle for spraying the wash water circulated by the pump into the drum, in the laundry amount detection step, the control unit drives the drive unit and detects an amount of the laundry accommodated in the drum so as to set a target water level, which is a target amount of wash water which is supplied into the tub after the completion of the wash water supply step, wherein in the wash water supply step, the control unit controls the water supply unit to supply the wash water into the tub such that a level of the wash water is lower than the target water level, drives the drive unit to accelerate the drum at a rotational speed in a state in which the laundry is attached to the drum and drives the pump when the drum is accelerated, so as to spray the wash water, circulated through the circulation nozzle, into the drum, and controls the water supply unit to supply the wash water into the tub until the target water level. wherein in the wash water supply step, the control unit controls the water supply unit to supply the wash water into the tub such that a level of the wash water is lower than the target water level, drives the drive unit to accelerate the drum at a rotational speed in a state in which the laundry is attached to the drum and drives the pump when the drum is accelerated, so as to spray the wash water, circulated through the circulation nozzle, into the drum, and controls the water supply unit to supply the wash water into the tub until the target water level.