Abstract:The abominable electromagnetic environment of the industrial field put forward higher and higher electromagnetic compatibility requirements to the hardware circuit system. In order to eliminate the fault of false tripping or false alarm etc caused by the interference of the electromagnetic interference, the paper explored the design strategy of electromagnetic compatibility in the industrial field hardware system. In this paper, it discussed on the influence of electromagnetic environment for the hardware system and the design concept of anti electromagnetic interference, made the anatomy on possible electromagnetic interference source and anti electromagnetic interference mechanism, and studied on the problem of electromagnetic compatibility design aiming at the behavior of digital circuits under electromagnetic interference. The experimental result demonstrated that the reasonable layout and circuit wiring and the good grounding are the necessary measures to be taken to resist electromagnetic interference. Engineering practice shows that the above mentioned electromagnetic compatibility design strategy is effective.