Abstract: Drilling accident is a huge threat to safe and efficient operation of directional drilling in underground coal mine. The common directional drilling accident was classified into drill rod sticking accident, breaking off accident and blowout accident, and drill rod sticking accident classified into formation collapse sticking, reducing sticking and sediment sticking. On the summary of cause of formation, preventive measures and treatment technology of these drilling accidents, the paper drew a conclusion that we must stick to principles of ‘prevention first and treatment second’. On the basis of actuality of the directional drilling accident in underground coal mine, the paper suggested that the specialized directional drilling accident preventive measures and treatment technology in underground coal mine should be developed immediately.