Abstract: In order to solve the space limitation of the coal mining in the 0.55 m ultra thin seam and to solve the high difficult problems of the fully-mechanized coal mining in the ultra thin seam, a new hydraulic powered support of the fully-mechanized coal mining, the coal mining and transportation equipment and the simplified full y-mechanized coal mining technique suitable for the mining of the ultra thin seam were researched and developed. With the electric and hydraulic automatic control fun ction different to the thick seam, a rational alteration between the walking space and the coal shearer was realized to ensure the rational space layout for the unmanned fully-mechanized coal mining process in the ultra thin seam and the equipment maintenance. Thus the fully-mechanized automatic coal mining in the ultra thin seam wa s realized.