Experimental and clinical data have suggested deleterious effects of long term right ventricular (RV) apical pacing on both systolic and diastolic function. Setpal pacing seemed to better preserve cardiac performance in patients with normal LV systolic function. We compared the feasibility of RV septal pacing compared to RV apical pacing. Method: we enrolled 134 patients who have implanted pacemaker from March 2004 to July 2006. RV lead was randomly fixed at RV apex or RV mid septum. Usually RV apical pacing was done with tine type lead, and RV septal pacing was done with screw type lead. Result: RV lead was positioned at RV apex in 78 pts (M:F-53:25, mean age 64) and RV mid septum in 56 pts (M:F=32:23, mean age 64). Pacemaker indication were sick sinus syndrome in 48 pts of RV apical pacing and 36 pts of RV septal pacing. The other were AV block. DDD or DDDR pacemaker was implanted in 62 pts in RV apical pacing 54 pts in RV septal pacing. For the others, VVI, VDD or VVIR pacemaker were implanted. Alhough pacing threshold was slight lower in RV apex group (RV apex 0.41mVX0.4ms vs RV septum 0.48mVX0.4ms, p<0.05), pacing threshold more than 1.0mVX0.4ms was found 3 pts in RV apical pacing. There was no one In RV septal pacing group, who showed pacing threshold more than 1.0mVX0.4 ms. Sensing value was not different (RV apex 9.93mV vs RV septum 9.50mV). 2 pts (2,5%) in RV apical pacing and 2 pts (3.5%) in RV septal pacing required reposition of RV lead because of RV lead dislodgement. In 1 pts (1.2%) in RV apical pacing, RV perforation and right hemothorax was developed after 5 days of implantation. Mean QRS width on ECG was 176ms in RV apical pacing group and 142ms in RV septal pacing group (p<0.01). Conclusion: RV septal pacing was feasible and safe as compared with RV apical pacing. Considering the deleterious effect of RV apical pacing, RV septal pacing could be done routinely in pacemaker implantation.