Abstract: Combining the practice of open-pit and underground combined mining in China in recent years, we carry out systematic, comprehensive and scientific research and classification of open-pit and underground combined mining modes, discuss and summarize the production and safe problems caused by open-pit and underground combined mining, and research various types safety control technology of open-pit and underground combined mining. All these provide basic technical basis for achieving the rational exploitation of coal resources and system theory research of open-pit and underground combined mining.