With the rapid development of high-speed integrated circuit technology and computer technology, not only has the application field of electronic products been expanded, but also brought about the complicated system, the mutual interference between various components or systems, the basic part of electronic products Is based on the PCB board to complete the various functions of the functional modules in the electronic product development process, the rapid evaluation of PCB board function module of the electromagnetic interference problem is to shorten the electronic product design cycle, improve product reliability and effective means. This paper is in this context, the design of a set of PCB board EMC problem automatic detection device to quickly, intuitively and accurately find possible sources of electromagnetic interference for electronic product design engineers to provide low-cost, fast testing method.