In off-pump coronary artery bypass grafting(OPCAB), a bloodless operative field has great influence on the quality of anastomosis. In addition, maintenance of distal coronary flow during anastomosis stabilizes hemodynamics. We introduced a new intracoronary shunt cannula, Mini Shunt Pro (MSP). MSP adopts the step-tip, which allows easy insertion and reduces the risk of intimal injury. The distal and proximal sides of the tips of MSP are 0.25 mm different in diameter, which improves its fitness to the coronary artery and enhances a bloodless operative field. This new shunt cannula is considered to be safe and useful for high-quality anastomosis in OPCAB.