A smokeless frying and baking machine, comprising: a lower shell, which is provided with a lower baking tray; a handle, which is rotatably mounted on the lower shell; an upper shell, which is provided with an upper baking tray, wherein the upper shell is rotatably mounted on the handle through a floating component, and the handle is configured to drive the upper shell to rotate back and forth to be close to the lower shell so that the upper baking tray and the lower baking tray are enclosed to form a frying and baking cavity or rotate away from the lower shell to the position of unfolding the tray; a fan component, wherein the lower shell is provided with an air channel, the fan component is mounted on the lower shell and is configured to generate negative pressure in the air channel to suck oil smoke generated by the lower baking tray and the upper baking tray, an angle detection component, wherein the angle detection component is mounted between the handle and the upper shell and is configured to detect the change of the angle between the handle and the upper shell;, characterised in: a rotating speed detection component, wherein the rotating speed detection component is mounted on the fan component and is configured to detect the actual rotating speed of the fan component; a controller, which is mounted on the lower shell and is electrically connected with the fan component, the angle detection component and the rotating speed detection component, respectively, wherein the controller is configured to calculate the actual volume of the frying and baking cavity according to the angle change, when the actual volume is less than the maximum volume, control the rotating speed of the fan component according to the desired rotating speed calculated by the actual volume, and then calculate the desired cooking duration of the current cooking stage of the frying and baking machine according to the actual rotating speed. a lower shell, which is provided with a lower baking tray; a handle, which is rotatably mounted on the lower shell; an upper shell, which is provided with an upper baking tray, wherein the upper shell is rotatably mounted on the handle through a floating component, and the handle is configured to drive the upper shell to rotate back and forth to be close to the lower shell so that the upper baking tray and the lower baking tray are enclosed to form a frying and baking cavity or rotate away from the lower shell to the position of unfolding the tray; a fan component, wherein the lower shell is provided with an air channel, the fan component is mounted on the lower shell and is configured to generate negative pressure in the air channel to suck oil smoke generated by the lower baking tray and the upper baking tray, an angle detection component, wherein the angle detection component is mounted between the handle and the upper shell and is configured to detect the change of the angle between the handle and the upper shell;, characterised in: a rotating speed detection component, wherein the rotating speed detection component is mounted on the fan component and is configured to detect the actual rotating speed of the fan component; a controller, which is mounted on the lower shell and is electrically connected with the fan component, the angle detection component and the rotating speed detection component, respectively, wherein the controller is configured to calculate the actual volume of the frying and baking cavity according to the angle change, when the actual volume is less than the maximum volume, control the rotating speed of the fan component according to the desired rotating speed calculated by the actual volume, and then calculate the desired cooking duration of the current cooking stage of the frying and baking machine according to the actual rotating speed. a rotating speed detection component, wherein the rotating speed detection component is mounted on the fan component and is configured to detect the actual rotating speed of the fan component; a controller, which is mounted on the lower shell and is electrically connected with the fan component, the angle detection component and the rotating speed detection component, respectively, wherein the controller is configured to calculate the actual volume of the frying and baking cavity according to the angle change, when the actual volume is less than the maximum volume, control the rotating speed of the fan component according to the desired rotating speed calculated by the actual volume, and then calculate the desired cooking duration of the current cooking stage of the frying and baking machine according to the actual rotating speed.