A recent survey of bone mineral density (BMD) in China recruited 7,042 healthy Han Chinese aged 20 years and older. The mean BMDs were different in gender, age, and region; the proportions of men and women older than 50 years with a high risk of osteoporosis were estimated as 10.4% and 31.2%, respectively A survey of BMD was completed during 2002-2006 in China. By three-stage sampling, a total of 7,042 healthy Han Chinese aged 20 years and older were recruited in ten cities: 2,694 subjects from Beijing, Tianjin, Haerbin, Lanzhou, and Yantai of northern China and 4,348 from Shanghai, Changsha, Chengdu, Haikou, and Foshan of southern China. Two dual X-ray absorptiometry (DXA) systems (Hologic and Lunar) were used with parallel measurements of the European spine phantoms in each center. The mean BMDs in age groups older than 50 and the peak bone mineral density (pBMD) at femoral neck and that at greater trochanter were higher for men than women, and the pBMDs for northern China were higher than those for southern China, ranging from 1% to 4%. This work has provided two useful references for the first time: one is the estimation of the proportion and number of individuals older than 50 years with a high risk of osteoporosis, 10.4% and 12.5 million men, 31.2% and 37.2 million women, which is important for health care planning and marketing projections, and another is the conversion equations for cross-calibration among different types of DXA instruments frequently used in China.