The invention relates to a vacuum chamber door safety protection device. The vacuum chamber door safety protection device is mounted at the bottom corner of one side of a handle of a vacuum chamber door. The vacuum chamber door safety protection device comprises a main cylinder. A piston rod of the main cylinder is connected with a supporting wheel. The supporting wheel is pushed upwards to support the vacuum chamber door when the vacuum chamber door is opened and closed; The supporting wheel is provided with an axial plug pin hole. The side face of the supporting wheel is provided with a ballplug pin, and the ball plug pin is plugged into the axial plug pin hole to lock the supporting wheel after the vacuum chamber door is opened and closed in place. Through the vacuum chamber door safety protection device, when the vacuum chamber door is opened and closed in place, the supporting wheel is driven by the main cylinder to support the vacuum chamber door, and accordingly, the situationthat the serious safety danger is caused when the vacuum chamber door topples towards one side under the action of gravity is effectively prevented. Meanwhile, occurrence of a safety accident caused by chamber toppling or overturning of the vacuum chamber door due to gravity center forward shifting caused by door opening in the maintenance process of a vacuum chamber is prevented.