Most of the current railway transportation system in the coal pit in China did not equip with the electric locomotive position system, thus the running speed and the location of the electric locomotive is not able to be accurately figured out. In this work, the piezoelectric accelerometer has been introduced into the locomotive position system in the coal pit to realize the positioning function through integrating over the collected acceleration value of the electric locomotive and solving out the speed and position. The basic principle of the piezoelectric acceleration sensor has been analyzed. The scheme of the locomotive position system in coal pit based on the piezoelectric accelerometer has been discussed. The software design of the system has been completed and the temperature drift and random errors of the piezoelectric accelerometer are calibrated and corrected. The piezoelectric acceleration sensor has been verified by the simulation experiment.