A washing machine comprising: a cabinet having a washing space disposed therein and a first opening through which laundry can be inserted into the washing space; and a door assembly configured to open or close the first opening, wherein the door assembly includes: a door unit including a guide duct having one side forming a second opening and the other side connected to the washing space, the door unit configured to be rotatable with respect to the cabinet; and a sub-door configured to open or close the second opening; wherein the door unit comprises a door body corresponding to the first opening and a door glass including an opening in the glass corresponding to the other side of the guide duct, and combined with the door body; characterised by: a sealing assembly configured to seal the other side of the guide duct, wherein the sealing assembly is configured to seal between the other side of the guide duct and the opening in the glass and comprises: a sealing rubber having elasticity and configured to cover a gap formed between the guide duct and the opening in the glass; and a sealing cap configured to cover the sealing rubber and coupled to at least one of the guide duct and the door glass. a cabinet having a washing space disposed therein and a first opening through which laundry can be inserted into the washing space; and a door assembly configured to open or close the first opening, wherein the door assembly includes: a door unit including a guide duct having one side forming a second opening and the other side connected to the washing space, the door unit configured to be rotatable with respect to the cabinet; and a sub-door configured to open or close the second opening; wherein the door unit comprises a door body corresponding to the first opening and a door glass including an opening in the glass corresponding to the other side of the guide duct, and combined with the door body; characterised by: a sealing assembly configured to seal the other side of the guide duct, wherein the sealing assembly is configured to seal between the other side of the guide duct and the opening in the glass and comprises: a sealing rubber having elasticity and configured to cover a gap formed between the guide duct and the opening in the glass; and a sealing cap configured to cover the sealing rubber and coupled to at least one of the guide duct and the door glass. a door unit including a guide duct having one side forming a second opening and the other side connected to the washing space, the door unit configured to be rotatable with respect to the cabinet; and a sub-door configured to open or close the second opening; wherein the door unit comprises a door body corresponding to the first opening and a door glass including an opening in the glass corresponding to the other side of the guide duct, and combined with the door body; characterised by: a sealing assembly configured to seal the other side of the guide duct, wherein the sealing assembly is configured to seal between the other side of the guide duct and the opening in the glass and comprises: a sealing rubber having elasticity and configured to cover a gap formed between the guide duct and the opening in the glass; and a sealing cap configured to cover the sealing rubber and coupled to at least one of the guide duct and the door glass. a sealing assembly configured to seal the other side of the guide duct, wherein the sealing assembly is configured to seal between the other side of the guide duct and the opening in the glass and comprises: a sealing rubber having elasticity and configured to cover a gap formed between the guide duct and the opening in the glass; and a sealing cap configured to cover the sealing rubber and coupled to at least one of the guide duct and the door glass.