Abstract: After analyzing the natural geographical conditions, geological conditions, hydrological characteristics in Pingdingshan coalfield, hydrogeological unints are divided based on the above analysis results. Pingdingshan coalfield is divided as three levelⅠhydrogeological units, two levelⅡhydrogeological units. Thoughts and measures of water-harm treatment are put forward based on the results of division of hydrogeological units and the practice of mine production.