The invention discloses a forced cooling device of a mobile switch cabinet. The device comprises a cabinet body and an air conditioner used for refrigeration. A top of the cabinet body is provided with an air box, and the air box is connected to the air conditioner through a heat insulation pipe. The air box is divided by a partition plate into a first air outlet box which integrally cools a spacein the cabinet body and a second air outlet box used for cooling an electrical component with high heating in the cabinet body. A first adjusting component for distributing cooling air of the air conditioner is arranged above the partition plate, and the first adjusting component and a second control component are used to control air volume entering into the first and second air outlet boxes. Then air flows with different temperatures can be sprayed out from the first and second air outlet boxes through a mixed flow mode. The cabinet body is integrally cooled, and targeted cooling can be performed on equipment with high heating so that the best heat dissipation effect can be reached and a problem of an equipment failure caused by an excessive local temperature can be avoided.