A washing machine comprising: a casing forming an exterior appearance of the washing machine; a tub for containing water suspended inside the casing; a drum for accommodating laundry rotatably provided inside the tub , the drum being provided with one or more lifters along its circumferential surface; a gasket provided between the casing and the tub and comprising a plurality of gasket nozzles spraying water into the drum and a plurality of connectors supplying water to the respective gasket nozzles ; the gasket nozzles being provided at both sides of a lower portion of the gasket , a first gasket nozzle configured to spray water upwardly toward the inside of the drum from a left lower portion of the gasket and a second gasket nozzle configured to spray water upwardly toward the inside of the drum from a right lower portion of the gasket , wherein each of the first and second gasket nozzle comprises a spray guidance surface for refracting an advancing direction of water supplied through the connector so as to spray the water toward an inside of the drum , and a plurality of protrusions arranged along a width direction of the spray guidance surface on the spray guidance surface ; a pump for pressure-feeding water to a pair of circulation hoses respectively connected to the first and second gasket nozzles , wherein the pump is configured to supply water simultaneously to the pair of circulation hoses ; a nozzle unit provided at an upper portion of the gasket , the nozzle unit comprising a spiral nozzle configured to spray water into the drum , and a controller configured to operate the pump while the laundry is repetitively lifted and dropped by a rotation of the drum . a casing forming an exterior appearance of the washing machine; a tub for containing water suspended inside the casing; a drum for accommodating laundry rotatably provided inside the tub , the drum being provided with one or more lifters along its circumferential surface; a gasket provided between the casing and the tub and comprising a plurality of gasket nozzles spraying water into the drum and a plurality of connectors supplying water to the respective gasket nozzles ; the gasket nozzles being provided at both sides of a lower portion of the gasket , a first gasket nozzle configured to spray water upwardly toward the inside of the drum from a left lower portion of the gasket and a second gasket nozzle configured to spray water upwardly toward the inside of the drum from a right lower portion of the gasket , wherein each of the first and second gasket nozzle comprises a spray guidance surface for refracting an advancing direction of water supplied through the connector so as to spray the water toward an inside of the drum , and a plurality of protrusions arranged along a width direction of the spray guidance surface on the spray guidance surface ; a pump for pressure-feeding water to a pair of circulation hoses respectively connected to the first and second gasket nozzles , wherein the pump is configured to supply water simultaneously to the pair of circulation hoses ; a nozzle unit provided at an upper portion of the gasket , the nozzle unit comprising a spiral nozzle configured to spray water into the drum , and a controller configured to operate the pump while the laundry is repetitively lifted and dropped by a rotation of the drum . <EOS>