Oven air duct system and oven

The utility model provides an oven air duct system which comprises an inner container and a fan cover arranged in the inner container, more than two supporting mechanisms are arranged on the inner container at intervals in the height direction, the side portion of the fan cover is provided with an air supply channel corresponding to the supporting mechanisms, the air supply channel is connected with an opening and closing device capable of controlling the opening degree of the air supply channel, and the inner container is provided with a sensing device. The opening and closing device responds to the sensing device to control the opening degree of the air supply channels, different opening and closing selections are made for all the air supply channels according to the layer number of the baking trays and food distribution, the air supply channels can be adjusted according to the single-layer or multi-layer baking trays, and the air path is made to conduct baking according to the specific layer position. The