Combination switch cabinet with fire extinguishing function and application method of combination switch cabinet

The invention relates to a combination switch cabinet with a fire extinguishing function and an application method of the combination switch cabinet. The combination switch cabinet comprises a cabinet body and a control system, wherein a plurality of convex parts are arranged on two inner side walls of the cabinet body at intervals; panels are placed on the opposite convex parts on two side walls; a hollow cavity is arranged in each convex part; liquid carbon dioxide is accommodated into each hollow cavity; an air outlet which is toward the inside of the cabinet body is formed in each hollow cavity and is provided with an electromagnetic valve; a smoke sensor and a temperature sensor are arranged in the cabinet body; and the control system receives signals of the smoke sensor and the temperature sensor and controls starting and stopping of each electromagnetic valve. The combination switch cabinet is simple in structure and convenient and safe to use.