 The current study is designed as a multicenter, randomized and prospective study aiming to compare the effect of two-stenting and simple stenting techniques in patients with complex bifurcation lesions. Based on the previous studies, the rate of 1-year target lesion failure events was around 25 after PCI with provisional stenting. And our previous data showed that this event at 12-month after DK crush procedure was 15. Considering the lost to follow-up, it is anticipated that up to 660 patients will be enrolled in the trial. All patients will have repeat angiography at 13 months, with clinical follow-up to 5 years. 