Objective To investigate the predicted risk of death and actual mortality in 1290 cases of off-pump coronary artery bypass grafting (OPCAB) and the clinical value of OPCAB in high-risk patients with coronary heart disease. Methods In 1290 cases, there were 762 males and 528 females aged from 21 to 88 years, with an average at 63.2±9.1 years. All cases were divided into 1998-2003 or 2004-2009 groups. From January 1998 to December 2003, there were 456 OPCAB surgeries, including 302 males and 154 females (mean age 58.1±6.9 years). From January 2004 to December 2009, there were 834 OPCAB surgeries, including 492 males and 342 females (mean age 64.3±8.5 years). The mortality, number of distal anastomosis, the average EuroSCORE, the complication rate (including perioperative myocardial infarction, stroke, new atrial fibrillation, acute renal failure, and respiratory insufficiency), ICU stay and tracheal intubation time were compared between the two groups. Results The average distal anastomosis was 3.28±0.81. The complication rate was 11.3% and operative mortality was 4.42%. ICU time, tracheal intubationtime and average EuroSCORE were 68.8±5.14 hours, 16.3±4.5 hours and 4.68±2.57, respectively. Between the two groups, the operative mortality, number of distal anastomosis, average EuroSCORE, the complications rate, ICU time and tracheal intubation time were significantly different. Mean EuroSCORE increased from 1.7 in 1998 to 7.2 in 2009, but mortality decreased from 8.6% to 3.13%. Conclusions The EuroSCORE plays an important role in predicting the risk of death in OPCAB. Contrary to the increased predictive risk of death, the actual OPCAB operative mortality significantly decreased. This phenomenon should be attributed to the expanded indications of surgery, technology development and comprehensive perioperative care and treatment.