This study was carried out to examine the safety and efficacy of balloon oversizing method using the patient height as a safe guide for balloon selection. The study consisted of 30 patients with pliable non calcified mitral valve with an echo score < 8. The mitral valve area was increased using the stepwise dilatation technique from 1.0 ± 0.3 before dilatation to 2.0 ± 0.4 after dilatation. Two patients (7%) developed DeNovo mitral regurgitation, and another two patients (7%) showed increase in the degree of regurgitation (from +1 before dilation to +2 after dilatation), none of them required surgical interference. They were clinically stable. The pressure gradient through the mitral valve showed significant drop from 18.1 ± 8.5 before to 6.1 ± 3.4 after dilatation. In conclusion, balloon oversizing method based on patient’s height is safe with respect to the state of subvalvular apparatus and the echo score. Selected balloon size should be 2-4 mm more than calculated one according to Hung’s formula height /10+10.