In China, 20% of the coal total reserves are low coal seam. Safe and efficient exploitation of gently-dipping close-range low coal seam not only reduce the waste of resources, but also to extend the mine life. Based on the geological conditions and the storage state in the median space of Da'anshan coal mine, analyze the in-situ rock stress laws of four mining methods (make single and compound mining respectively in the coal pillars and no coal pillar) by similarity simulation theory and numerical simulation. The rooffall state and the strata-pressure laws of exploiting in gently-dipping close-range low coal seam are found. Furthermore, there are four experiments by dint of similar material simulation experiment and rock's physical mechanical experiment for the coal seam with different mining methods. It is better that taking no coal pillar and single seam mines coal in flat dipping girdle in security and economy by comparison. The simulation and the experimental results are very important in the other pertinent theoretical researches and productive practices.
Coal is always the major energy source in China due to constraint of energy kinds and reserves. It is very rich. The proportion of coal still is about 70\% in total primary energy since it has decreased in recent years.[1[ It shows that coal is in an important position in China's national economy. With continually mined, most of the coal mines has been at the stages of deep thin-seam mining. Mining the thin seams can not only reduce the waste of resources, but also help to extend the life of coal mine. Hence it is a major problem that how to mine the composite thin seams safely and effectively. Many experts at home and abroad advance a number of ways for the inclined thin seam mining.
