Abstract: Objective: To explore the calcium metabolism in normal women and some gestational diabetes pregnant women pregnancy women. Methods: The women were divided into 3groups:(1) gestational diabetes (n=31);(2) Normal third trimester (n=60);(3) nonpregnant (n=30). Blood and urine samples were collected at 8:00a. m. following an overnight fast. in same day tibia SOS was measured by ultrasound scanner. BGP were considered evaluted for formation markers,and the urinary calcium and Dpy creatinine ratio evaluated for bone absorption markers. Total calcium and free-calcium were measured. Phosphorus,magnesium and total protein were measured. Results: As compared with Normal third trimester nonpregnant tibia SOS in gestational diabetes women declined. BGP,total calcium,Phosphorus,magnesium and total protein decreased. The urinary calcium and Dpy creatinine ratio increased. Conclusions: AS compared with normal third trimester tibia SOS in gestational diabetes women decreased;bone formation decreased;bone asporption increased.