Objective To establish an effective method of isolating and culturing circulating fibrocytes from human peripheral blood and study the relationship between the expression specific molecule markers expression and the morphological characteristics. Methods Total peripheral blood leukocytes were isolated from human peripheral blood by being centrifuged over FicollPaque and cultured in DMEM supplemented with 20% fetal calf serum. Adhered cells were detected with immunocytochemistry, FCM and electron microscopy. The collagen synthesis was studied by measurement of the hydroxyproline concentration in the medium with chemical method. Results After 9 days cultue in vitro, CD34,CD45 and collagen Ⅰ staining was positive and 83.5% of these cells secreted collagen Ⅰ detected by FCM. Electron microscopy of circulating fibrocytes showed morphological characteristics of fibroblasts. The hydroxyproline concentration in the medium was 11.17%mg/L, which was statistically and significantly different compared with 8.07mg/L in the control medium(P<0.01).Conclusion Circulating fibrocytes could not only be isolated effectively from human peripher