A cooking appliance comprising: a casing having a cavity and an upper space divided from the cavity, therein; a door disposed at front of the casing and configured to open and close the cavity; a panel unit disposed at front of the casing at a height different from a height of the door, and movable from a first position to a second position; and a hinge module connecting the casing and the panel unit to each other, the hinge module is disposed in the upper space, wherein the hinge module comprises: a hinge housing disposed in the upper space; and a driving arm protruding forwards from the upper space and connected to the panel unit, the driving arm having a first end connected to the hinge housing, and a second end protruding forwards from the upper space of the cavity to be rotatably connected to the panel unit, wherein the driving arm is connected to a plurality of hinge coupled portions provided in the panel unit; wherein the driving arm comprises: a first driving arm having a first end rotatably connected to the hinge housing; and a second driving arm configured to be operated in conjunction with the first driving arm, and having a first end rotatably connected to the hinge housing; wherein both a second end of the first driving arm and a second end of the second driving arm are connected to the panel unit; and wherein in an opening process of the panel unit, the second driving arm is stored in the first driving arm, and the first driving arm and the second driving arm are overlapped with each other. a casing having a cavity and an upper space divided from the cavity, therein; a door disposed at front of the casing and configured to open and close the cavity; a panel unit disposed at front of the casing at a height different from a height of the door, and movable from a first position to a second position; and a hinge module connecting the casing and the panel unit to each other, the hinge module is disposed in the upper space, wherein the hinge module comprises: a hinge housing disposed in the upper space; and a driving arm protruding forwards from the upper space and connected to the panel unit, the driving arm having a first end connected to the hinge housing, and a second end protruding forwards from the upper space of the cavity to be rotatably connected to the panel unit, wherein the driving arm is connected to a plurality of hinge coupled portions provided in the panel unit; a hinge housing disposed in the upper space; and a driving arm protruding forwards from the upper space and connected to the panel unit, the driving arm having a first end connected to the hinge housing, and a second end protruding forwards from the upper space of the cavity to be rotatably connected to the panel unit, wherein the driving arm is connected to a plurality of hinge coupled portions provided in the panel unit; a first driving arm having a first end rotatably connected to the hinge housing; and a second driving arm configured to be operated in conjunction with the first driving arm, and having a first end rotatably connected to the hinge housing; wherein both a second end of the first driving arm and a second end of the second driving arm are connected to the panel unit; and wherein in an opening process of the panel unit, the second driving arm is stored in the first driving arm, and the first driving arm and the second driving arm are overlapped with each other.