A top-loading washing machine, comprising a housing, a drum with two ends enclosed being mounted in the housing; a door body openable and closable being disposed on a side wall of the drum; characterized in that the top-loading washing machine further comprises a drainage port formed in the side wall of the drum; a sealing valve mounted at the drainage port; a valve core of the sealing valve is subjected to centrifugal force to open the drainage port when the drum rotates at a high speed, and seals the drainage port when the drum rotates at a low speed or is stationary; the sealing valve comprises a valve plug pillar correspondingly mounted at the drainage port formed in the side wall of the drum, and a balancing weight hinged to an upper end of the valve plug pillar; a sealing valve mounting structure is fixedly mounted on the side wall of the drum; and a return spring is clamped between the sealing valve mounting structure and the valve plug pillar; the sealing valve mounting structure comprises a supporting plate mounted on an inner side wall of the drum; a middle portion of the supporting plate is provided with a through hole corresponding to the drainage port formed in the side wall of the drum; a clearance is reserved between the supporting plate and the side wall of the drum to form a space for the valve core of the sealing valve moving up and down; a mounting sleeve is fixedly mounted on an upper side of the supporting plate; an inner side through hole of the mounting sleeve is coaxially provided correspondingly to the through hole formed in the supporting plate, so as to mount the valve plug pillar of the sealing valve in the inner side through hole coaxially in a manner of being movable up and down. a housing, a drum with two ends enclosed being mounted in the housing; a door body openable and closable being disposed on a side wall of the drum; characterized in that the top-loading washing machine further comprises a drainage port formed in the side wall of the drum; a sealing valve mounted at the drainage port; a valve core of the sealing valve is subjected to centrifugal force to open the drainage port when the drum rotates at a high speed, and seals the drainage port when the drum rotates at a low speed or is stationary; the sealing valve comprises a valve plug pillar correspondingly mounted at the drainage port formed in the side wall of the drum, and a balancing weight hinged to an upper end of the valve plug pillar; a sealing valve mounting structure is fixedly mounted on the side wall of the drum; and a return spring is clamped between the sealing valve mounting structure and the valve plug pillar; the sealing valve mounting structure comprises a supporting plate mounted on an inner side wall of the drum; a middle portion of the supporting plate is provided with a through hole corresponding to the drainage port formed in the side wall of the drum; a clearance is reserved between the supporting plate and the side wall of the drum to form a space for the valve core of the sealing valve moving up and down; a mounting sleeve is fixedly mounted on an upper side of the supporting plate; an inner side through hole of the mounting sleeve is coaxially provided correspondingly to the through hole formed in the supporting plate, so as to mount the valve plug pillar of the sealing valve in the inner side through hole coaxially in a manner of being movable up and down.