Abstract:The stability characteristics of main seam roof in Yanzhou coalfield are analyzed. And the different influencing factors are generalized as the sedimentary characteristics,tectonic characteristics,mechanical property and some others. From sediment analysis,the main seam roof is divided into hardness-upward,softness-upward or their compound. From tectonic characteristics,the main seam roof is divided into super structure-development,structure-development,middle structure-development,and nondevelopment. From rock strength,the main seam roof is divided into extra-high intensity,high intensity,middle intensity,and low intensity. All factors are comprehensively analyzed,and based on analytical hierarchy process(AHP) and fuzzy mathematics method,the stability characteristics of main seam roof are evaluated in Yanzhou coalfield. The stability roof are divided into four grades:super stability,stability,middle stability and instability. The zone of super stability is thick coarse sandstones,with few structures and extreme high strength. The zone of stability is medium-bedded fine sand and silt with a few structures and intermittent,and high strength. The zone of middle stability are silt and mudstone with many structures of partly cutting through and medium strength. The zone of instability are mudstone and seam with large quantity and continuous structures and low strength.