As a new technology, the directional drilling for underground coal mine has been applied in fields such as gas drainage, water control， geological exploration and accurate drilling borehole engineering. By the popularization and application in more than 30 mines of China, the horizontal directional drilling technology and the equipments for underground coal mine have been gradually improved with new progress; ZDY12000LD directional drilling rig, MWD by mud pulse transmission system, geo-steering drilling device and compound directional drilling technology have been formed. 1881m directional drilling borehole in coal seam and 1026m directional drilling borehole in rock were completed in underground coalmine, which show the advantages of ZDY12000LD rig in large power, high capability in drilling and accident processing and high measurement accuracy of MWD by mud pulse transmission system, by the combination of directional drilling with down-hole motor and rotary drilling technologies, the high drilling efficiency is achieved with smooth borehole wall, less cuttings and small borehole curvature.