The present invention relates to an out-of-plane ultrasonic guiding device. The out-of-plane ultrasonic guiding device comprises a telescopic arm, a fixed end of the telescopic arm is provided with arotating sleeve, an axial center line of the rotating sleeve is superposed with a central axis of an ultrasonic probe, and a transverse axis of the telescopic arm is vertical to the central axis; an telescopic end of the telescopic arm is provided with a rotating mechanism, the rotating mechanism is provided with a telescopic positioning sleeve and a microcomputer, an ultrasonic machine measures avertical distance between an intersection point of the central axis and the skin and a puncture end point, the positioning sleeve measures a vertical length between a puncture starting point and thetransverse axis, the microcomputer calculates rotating angles of the rotating mechanism according to vertical distance, vertical length and horizontal distance data, and the rotating mechanism drivesthe axis of the positioning sleeve to rotate to coincide with a straight line determined by the puncture starting point and the puncture end point according to the rotating angles. Through the telescopic arm, rotating mechanism, telescopic positioning sleeve, and microcomputer the device can realize rotation of the positioning sleeve of a positioning puncture needle, and thus can accurately position the puncture angles of the puncture needle out of a plane.