The invention relates to the field of printers, and discloses a printer. The printer is characterized by comprising a ventilation device, the ventilation device comprises an air supply device and an air outlet arranged in a paper outlet area of the printer; a communication interface for receiving a printing task; a printing mechanism; a controller is used to control the printing mechanism to execute a printing task; the controller is configured to analyzing the received printing task to obtain the workload of the printing task; whether the workload is larger than a set threshold value or not is judged; when the working amount is judged to be larger than the set threshold value, the ventilation device is started.