Abstract: During the operation of the vertical frozen holes in Donghuantuo Coal Mine,Kailuan,JTD-3K directional gyroscope and deflector which can be withdrawn with the string were used for directional correction,with mission success rate of 100%.Besides,the operational measurements are much more improved,e.g.correct selection of deflecting position,delimitation of pre-deflecting area,determination of optimum deflector working angle and proper operation,etc.