Background: Although final kissing balloon postdilatation (FKB) is one of the most important determinants of angiographic and clinical outcomes after ���crush��� technique, consensus for optimal standard method of FKB has been lacking. We aimed to evaluate the effect of dilating force during FKB on optimal result after bifurcation stenting with ���modified mini-crush technique��� (MMCT). Methods: After two coronary angioplasty balloons with different diameter (3.5 mm and 2.5 mm) were inserted side by side into experimental coronary phantom tube, the balloons were inflated with equal pressure and then with equal dilating force derived from Laplace law, sequentially. Magnetic resonance imaging was performed for comparing expansion of the balloons in different dilating settings. Five de novo bifurcation lesions of 5 patients were treated with MMCT and dilated with equal dilating force and equal dilating pressure, sequentially. Angiographic and intravascular ultrasound (IVUS) results were analyzed. Results: In experimental model, the ratio of diameter and cross-sectional area between the two balloons showed more similar results with the intended results (diameter ratio, 2.50mm/3.50mm = 0.71; area ratio, 4.91mm²/9.62mm² = 0.51) after equal dilating force FKB (diameter ratio, 2.02mm/2.88mm = 0.70; area ratio, 4.62mm²/9.07mm² = 0.51) compared to equal pressure FKB (diameter ratio, 1.86mm/3.07mm = 0.61; area ratio, 4.26mm²/9.58mm² = 0.44). IVUS analysis demonstrated minimal stent area (MSA) at side branch ostium tended to be larger after equal dilating force compared to equal pressure FKB (3.98짹0.29 mm² vs. 4.48짹0.67 mm², p=0.182). In contrast, MSA at main vessel was quite same between the two FKB methods (8.38짹1.50 mm² vs. 8.64짹1.67 mm², p=0.357). Conclusions: Equal dilating force other than equal dilating pressure might be more ideal for FKB to achieve optimal result after bifurcation stenting with MMCT.