Abstract: First, the track electrical circuits and axle counting are defined, then track inspection devices described in detail. Combining with rail traffic signal project status analysis, comparison design concept of axle counting equipment used as rail test equipment is obtained. The composition of axle counting equipment is described in detail and analyzed under various conditions. The track inspection principle and corresponding design principle are outlined for different circumstances taking into account axle track inspection equipment installation interface and notes. finally, application of axle counting system is introduced.