Abstract: According to the priori unknown unfavorable condition of the equipment fault mode applied in the coal preparation plant, the discriminance method of the health trust for the equipment applied in the coal preparation plant was provided. According to the time sequence established by the vibration data from the measureme nt and sampling of the drum bearing seats in the coal preparation plant, the normal operation features of the equipment were selected as the modal set of the normal w orking and a prediction method of the health trust degree was established based on the modal. Among them, the selection of the feature parameters was mainly in the li ght of the frequency closeness degree. With the training conducted on the vibration data measured from the drum shaft seats, an optimal modal set was established an d was applied to make the judgement on the other vibration measured data of the drum shaft seats. Then the optimal modal set could be applied to judge the drum shaft seats whether out off the normal working status and to have the discriminance basis of the equipment health trust degree. The discriminance method of the equipment h ealth trust degree applied in the coal preparation plant was applied to the monitoring and measuring of the equipment applied in the Xinglongzhuang Coal Preparation P lant and the results showed that the method could distinguish the normal and fault status and could have the suitable calculation features.