The invention belongs to the technical field of dust prevention equipment, particularly relates to a dust prevention system for mechanical equipment, and aims to overcome the defects that an existing dust prevention system cannot achieve dust prevention and radiating at the same time, is poor in dust prevention effect, and the like. According to the technical scheme, the dust prevention system comprises a mechanical equipment mounting box and is characterized in that a rectangular hole is formed in the front panel of the mechanical equipment mounting box, box doors are fixed on the front panel of the mechanical equipment mounting box through hinges, a through hole is formed in the lateral wall at one end of the mechanical equipment mounting box, and an induced draft fan is mounted in the through hole; a through hole is formed in each of the lateral wall at the one end, away from the induced draft fan, of the mechanical equipment mounting box and in the back plate of the mechanical equipment mounting box, and a first air inlet pipe and a second air inlet pipe are respectively welded into the two through holes. The dust prevention system has the advantages that the system integrates functions of dust prevention and radiating, and the service life of the mechanical equipment is effectively prolonged.