A laundry treatment apparatus, comprising: an outer tub; a hole-less inner drum rotatably arranged in the outer tub and configured to hold water; a water storage cavity arranged on the outer tub and configured to store water overflowing from the inner drum; a drain pipe in communication with the water storage cavity; a drain pump configured to discharge the water in the water storage cavity through the drain pipe; a heating member arranged in the water storage cavity, wherein a part of the inner drum extends into the water storage cavity, and the heating member is configured to heat the inner drum via the water in the water storage cavity, and wherein the heating member is configured to heat the water in the inner drum via the inner drum; a water level detecting device configured to detect a water level in the water storage cavity; and a control device connected to the drain pump and the water level detecting device, wherein the control device is configured to acquire the water level detected by the water level detecting device, and control the drain pump to be activated according to the detected water level, to prevent the water overflowing into the water storage cavity from flowing back into the inner drum; and characterized by: a three-way member arranged on the drain pipe, wherein the three-way member comprises: a first port and a second port, wherein each of the first port and the second port is connected to a respective one of interfaces of the drain pipe to connect the three-way member to the drain pipe; and a third port in communication with a chamber of the outer tub or external atmospheric pressure and configured to eliminate an air pressure difference of the drain pipe at the three-way member. an outer tub; a hole-less inner drum rotatably arranged in the outer tub and configured to hold water; a water storage cavity arranged on the outer tub and configured to store water overflowing from the inner drum; a drain pipe in communication with the water storage cavity; a drain pump configured to discharge the water in the water storage cavity through the drain pipe; a heating member arranged in the water storage cavity, wherein a part of the inner drum extends into the water storage cavity, and the heating member is configured to heat the inner drum via the water in the water storage cavity, and wherein the heating member is configured to heat the water in the inner drum via the inner drum; a water level detecting device configured to detect a water level in the water storage cavity; and a control device connected to the drain pump and the water level detecting device, wherein the control device is configured to acquire the water level detected by the water level detecting device, and control the drain pump to be activated according to the detected water level, to prevent the water overflowing into the water storage cavity from flowing back into the inner drum; and characterized by: a three-way member arranged on the drain pipe, wherein the three-way member comprises: a first port and a second port, wherein each of the first port and the second port is connected to a respective one of interfaces of the drain pipe to connect the three-way member to the drain pipe; and a third port in communication with a chamber of the outer tub or external atmospheric pressure and configured to eliminate an air pressure difference of the drain pipe at the three-way member.