A method of controlling a washing machine that includes a tub, a drum rotatably disposed in the tub, at least one nozzle spraying water toward the drum, a washing motor rotating the drum, and a circulation pump circulating water discharged from the tub, the method including: supplying a first level of water into the tub; operating the circulation pump at a first speed; controlling a rotation of the drum to repeatedly alternate between an acceleration and a deceleration so that laundry in the drum alternates between maintaining contact with an inner surface of the drum and separating from the inner surface of the drum; further supplying water to the tub to raise the first water level to a second water level.