A cooking appliance for cooking food, the cooking appliance comprising: a main body having a cooking chamber formed therein, the main body including a back surface portion and a side surface portion; a fan cover installed on the back surface portion and forming an accommodation space, the fan cover having an exhaust port configured to exhaust air toward the side surface portion; a convection fan accommodated in the accommodation space and configured to generate a first predetermined air flow pattern of air discharged through the exhaust port into the cooking chamber in case of a first predetermined distance between the side surface portion and the exhaust port which provides an air circulation flow in which the air discharged toward the side surface portion through the exhaust port flows toward a front side of the cooking chamber at at least a predetermined rate; and an airflow guide member provided between the exhaust port and the side surface portion, the airflow guide member being configured to guide air discharged through the exhaust port into the cooking chamber according to the first predetermined air flow pattern, wherein the main body comprises an extended connection surface portion which is formed in the same plane as the back surface portion and is provided between the back surface portion and the side surface portion, wherein the exhaust port and the side surface are spaced apart from each other by a second predetermined distance which is longer than the first predetermined distance, and wherein the airflow guide member comprises: a coupling portion formed parallel to the extended connection surface and coupled to the extended connection surface portion; and a guide portion protruding from the coupling portion toward a door for opening and closing the cooking chamber, the guide portion being configured to guide air discharged through the exhaust port into the cooking chamber toward the door, the door being provided opposite to the back surface portion, wherein a distance between the exhaust port and the guide portion is shorter than the second predetermined distance between the exhaust port and the side surface portion, characterized in that the airflow guide member is formed in a "λ" shape a main body having a cooking chamber formed therein, the main body including a back surface portion and a side surface portion; a fan cover installed on the back surface portion and forming an accommodation space, the fan cover having an exhaust port configured to exhaust air toward the side surface portion; a convection fan accommodated in the accommodation space and configured to generate a first predetermined air flow pattern of air discharged through the exhaust port into the cooking chamber in case of a first predetermined distance between the side surface portion and the exhaust port which provides an air circulation flow in which the air discharged toward the side surface portion through the exhaust port flows toward a front side of the cooking chamber at at least a predetermined rate; and an airflow guide member provided between the exhaust port and the side surface portion, the airflow guide member being configured to guide air discharged through the exhaust port into the cooking chamber according to the first predetermined air flow pattern, wherein the main body comprises an extended connection surface portion which is formed in the same plane as the back surface portion and is provided between the back surface portion and the side surface portion, wherein the exhaust port and the side surface are spaced apart from each other by a second predetermined distance which is longer than the first predetermined distance, and wherein the airflow guide member comprises: a coupling portion formed parallel to the extended connection surface and coupled to the extended connection surface portion; and a guide portion protruding from the coupling portion toward a door for opening and closing the cooking chamber, the guide portion being configured to guide air discharged through the exhaust port into the cooking chamber toward the door, the door being provided opposite to the back surface portion, wherein a distance between the exhaust port and the guide portion is shorter than the second predetermined distance between the exhaust port and the side surface portion, characterized in that the airflow guide member is formed in a "λ" shape a coupling portion formed parallel to the extended connection surface and coupled to the extended connection surface portion; and a guide portion protruding from the coupling portion toward a door for opening and closing the cooking chamber, the guide portion being configured to guide air discharged through the exhaust port into the cooking chamber toward the door, the door being provided opposite to the back surface portion, wherein a distance between the exhaust port and the guide portion is shorter than the second predetermined distance between the exhaust port and the side surface portion, characterized in that the airflow guide member is formed in a "λ" shape