A garment processing apparatus including: a duct provided at an upper part of a drum, configured to form a flow passage passing through a heat exchanger installed at the inside, and having an inclined bottom surface; a fan motor installed at the duct to move air inside the duct; a condensed water discharge tray provided at a bottom surface of the duct, wherein condensed water generated from air passing through the heat exchanger is collected in the condensed water discharge tray; a drain installed at a lower part of the drum and configured to discharge the condensed water collected in the condensed water discharge tray to the outside; and a condensed water discharge pipe connecting the condensed water discharge tray and the drain to allow the condensed water to flow, wherein the condensed water collected in the condensed water discharge tray prevents a backflow of fluid from the drain tray to the condensed water discharge part through the condensed water discharge pipe caused by a pressure difference generated by a drive of the fan motor.