Osteocalcin, a bone-derived polypeptide, was recently found to have hormonal function associated with metabolic disorders and atherosclerosis. Few studies have examined the association between circulating osteocalcin and coronary heart disease (CHD) risk. The aim of the present study was to investigate whether serum osteocalcin concentration was associated with CHD risk and metabolic profiles in Chinese adults. A total of 461 subjects (243 with CHD and 218 without CHD) who underwent coronary angiography were included. Serum osteocalcin, glucose, lipid profiles, and other biochemical markers were measured. Severity of coronary atherosclerosis was estimated by number of diseased vessels. Results showed that serum osteocalcin levels were significantly lower in the CHD group (12.2 ng/ml, 9.5 to 15.1) than in the non-CHD group (13.6 ng/ml, 10.7 to 18.0, p = 0.001) and were significantly decreased with the increasing of number of diseased vessels (p = 0.005). Serum osteocalcin concentration was inversely correlated with fasting and post load 2 hour plasma glucose and hemoglobin A(1c) (p = 0.044, 0.043, and 0.011, respectively), adjusting for CHD status. Odds ratios (95% confidence intervals) of CHD across increasing quartiles of serum osteocalcin were 0.68 (0.42 to 1.12), 0.59 (0.36 to 0.98), and 0.40 (0.23 to 0.69). The test for trend was significant (p = 0.0007). Adjusting for age, body mass index, and other conventional risk factors for CHD did not appreciably change the results. Spline regression analyses indicated a linear relation between serum osteocalcin level and CHD risk. In conclusion, our data indicate that serum osteocalcin level was associated with decreased risk of CHD and protective metabolic changes in Chinese adults.