Context .- Although primary bone tumors are extremely rare, the literature suggests that there are variations in the epidemiologic characteristics in different populations. The most frequently cited epidemiologic characteristics of primary bone tumors are derived from a large US series (Mayo Clinic), with no comparable study thus far performed in China. Objective .- To identify any potential epidemiologic differences between Chinese patients and a US series of patients. Design .- We performed a comparison study between 9200 patients treated at Beijing Ji Shui Tan Hospital (JST) and 10 165 patients treated at Mayo Clinic (MC), Rochester Minnesota. Detailed epidemiologic features were analyzed. Results .- We found that giant cell tumor and osteosarcoma have significantly higher incidences in the JST than the MC patients (P < .001). However, JST patients had a significantly lower incidence of Ewing sarcoma, chordoma, fibrosarcoma, myeloma, and malignant lymphoma (P < .001). For most benign and malignant bone tumors, the Chinese cohort had a more distinct male predominance than the US cohort. Malignant bone tumors had a monomodal age distribution in the JST patient group, with a bimodal age distribution in the MC cohort. Also, there were was a predilection for tumors of the femur and tibia among the JST patients (P < .001). Conclusions .- Our data confirm that epidemiologic variations of primary bone tumors exist in different populations. Factors that may contribute to these observed differences are proposed and discussed.