The present invention provides a blocking method of distance protection swing of a high voltage transmission line, the swing blocking technique in the high voltage transmission line distance protection has always been one of the focus discusses. The technical scheme of the invention has two swing blocking methods having different principles, automatically selecting one swing blocking method according the length of the protection line. When the protection judgement is a short line, periodic oscillation change rate and the position of the apparent impedance are real-time detected by a stackablecounter, the dwell is relatively adjusted and the relieved, the method is not only applied to the great round covering the small round type operation characteristics, but also applied to the great quadrilateral covering the small quadrilateral type operation characteristics; when the protection judgement is a long transmission line, the swing blocking pattern fpr detecting Ucos fai and its changerate is utilized. Two patterns is automatically switched by the command set in a microcomputer software program, according to the size of the setting impedance.