A dishwasher, comprising: an inner washing tub having a washing cavity defined therein; a spray arm disposed in the inner washing tub; a heating device configured to heat water for washing and having a to-be-heated water inlet and a heated water outlet; a washing pump having a washing pump inlet and a washing pump outlet; a water collection tank disposed at a bottom of the inner washing tub, wherein the water collection tank has: a water collection cavity in communication with the washing cavity and having a washing outlet connected to the washing pump inlet; a flow distribution cavity having an opening; and a spray arm port, a washing pump port, and a second heating device port that are in communication with the flow distribution cavity, wherein the spray arm port is connected to the spray arm, wherein the washing pump port is connected to the washing pump outlet, and wherein the second heating device port is connected to the heated water outlet; and a water distribution valve assembly comprising: a valve seat having a first heating device port, wherein the valve seat is connected to the water collection tank and configured to block the opening of the flow distribution cavity, and wherein the first heating device port is in communication with the flow distribution cavity and connected to the to-be-heated water inlet; and a valve core movably disposed in the flow distribution cavity to allow the spray arm port to switch from communicating with the washing pump port to the second heating device port, wherein the valve core is configured to: block the first heating device port when the spray arm port is in communication with the washing pump port, and open the first heating device port when the spray arm port is in communication with the second heating device port to allow the washing pump port to be in communication with the first heating device port. an inner washing tub having a washing cavity defined therein; a spray arm disposed in the inner washing tub; a heating device configured to heat water for washing and having a to-be-heated water inlet and a heated water outlet; a washing pump having a washing pump inlet and a washing pump outlet; a water collection tank disposed at a bottom of the inner washing tub, wherein the water collection tank has: a water collection cavity in communication with the washing cavity and having a washing outlet connected to the washing pump inlet; a flow distribution cavity having an opening; and a spray arm port, a washing pump port, and a second heating device port that are in communication with the flow distribution cavity, wherein the spray arm port is connected to the spray arm, wherein the washing pump port is connected to the washing pump outlet, and wherein the second heating device port is connected to the heated water outlet; and a water collection cavity in communication with the washing cavity and having a washing outlet connected to the washing pump inlet; a flow distribution cavity having an opening; and a spray arm port, a washing pump port, and a second heating device port that are in communication with the flow distribution cavity, wherein the spray arm port is connected to the spray arm, wherein the washing pump port is connected to the washing pump outlet, and wherein the second heating device port is connected to the heated water outlet; and a water distribution valve assembly comprising: a valve seat having a first heating device port, wherein the valve seat is connected to the water collection tank and configured to block the opening of the flow distribution cavity, and wherein the first heating device port is in communication with the flow distribution cavity and connected to the to-be-heated water inlet; and a valve core movably disposed in the flow distribution cavity to allow the spray arm port to switch from communicating with the washing pump port to the second heating device port, wherein the valve core is configured to: block the first heating device port when the spray arm port is in communication with the washing pump port, and open the first heating device port when the spray arm port is in communication with the second heating device port to allow the washing pump port to be in communication with the first heating device port. a valve seat having a first heating device port, wherein the valve seat is connected to the water collection tank and configured to block the opening of the flow distribution cavity, and wherein the first heating device port is in communication with the flow distribution cavity and connected to the to-be-heated water inlet; and a valve core movably disposed in the flow distribution cavity to allow the spray arm port to switch from communicating with the washing pump port to the second heating device port, wherein the valve core is configured to: block the first heating device port when the spray arm port is in communication with the washing pump port, and open the first heating device port when the spray arm port is in communication with the second heating device port to allow the washing pump port to be in communication with the first heating device port.