The present invention discloses a method for eliminating atrial far-field signals in ventricular channels for an implantable cardiac pacemaker. The method includes the following steps that: 1) if atrial and ventricular sensing events occur simultaneously in an atrial and ventricular sensing window in a VA interval, the following processing is carried out: 1, if a VV interval is larger than 300ms, current ventricular sensing is ignored, a 100ms safety AV interval is enabled, and 2, if the VV interval is smaller than or equal to 300ms, atrial and ventricular sensing is caused by T waves, and atrial sensing and ventricular sensing are simultaneously ignored, and a 100ms atrial and ventricular absolute refractory period is enabled; and 2) in the AV interval of the atrial sensing, a 50ms long-field signal detection window is enabled, if a ventricular sensing event is detected in the window, and current ventricular sensing is ignored, and a 100ms safety AV interval is enabled, ventricular safety pacing is realized at the tail end of a ventricular sensing window. With the method of the invention adopted, the suppression of ventricular pacing pulses caused by cross sensing can be avoided, and therefore, the life of a patient having atrioventricular block can be effectively protected.