Abstract: In the construction of mine-used narrow-rail vehicle transportation monitoring system, proximity sensors are required to locate the wheels to detect the exact location of the mine car. Proximity sensors require some stability and detection accuracy. In view of this demand, a mineral proximity sensor is developed, the key components of the proximity sensor are analyzed and studied, the solution is determined and the actual test is carried out. An important component of the proximity sensor is the oscillating coil. The magnetic-core shape and coil material have a great influence on the oscillating coil, and the combination of several different shapes and wires is tested and studied, sensors were made and field applications were carried out.