In view of the difficult problem of fault detection of electromechanical equipment in coal preparation plant, the Xinjing Coal Preparation Plant of Yangquan Coal Industry Group was taken as an example to study the intelligent detection of mechanical and electrical equipment failure. The fault detection principle and workflow were introduced, and the fault detection server was designed. Practice showed that the sensors and relays collected the operating parameters of the equipment, and the intelligent system found the cause of the fault and made a judgment, which realized the intelligent technology of actively judging and confirmed the fault, eliminated the hidden troubles and ensured the stable operation of the electromechanical equipment of the coal preparation plant.