To assess the indications and clinical outcome of minimally invasive coronary artery bypass grafting with mini-sternotomy and cardiopulmonary bypass (MICS-CABG) for patients with multiple coronary artery disease, left main trunk stenosis and/or concomitant heart diseases, we examined results in 17 patients (mean age 62.5 years) who underwent MICS-CABG. The average number of distal anastomoses was 2.2 anastomoses/patient. The category of the coronary lesions was the left main trunk in 6 patients, triple vessel disease in 7, double vessel disease in 3, and left anterior descending artery stenosis with aortic regurgitation in 1 patient. Each operative procedure through the mini-sternotomy was easily and completely performed in all patients. By means of postoperative coronary angiography, full patency without stenosis in all grafts was recognized in 95.0%. Immediately after the MICS-CABG, all patients showed quick recovery of respiration, and postoperative admission duration significantly decreased compared with standard CABG with full sternotomy. The above results suggest that MICS-CABG is one of the procedures of choice for patients with multiple coronary artery disease, left main trunk stenosis and/or concomitant heart diseases.