To evaluate the efficacy and safety of comprehensive prophylaxis for deep venous thrombosis(DVT) after proximal femur fractures in geriatric patients. Methods From July 2003 to May 2006, 157 geriatric patients with proximal femur fractures treated with operation were divided into prophylaxis group and control group randomly. There were 82 patients (34 males, 48 females, aged 65-97 years) in prophylaxis group, 30 with femoral neck fracture and 52 with intertrochanteric fracture of femur. There were 75 patients (33 males, 42 females, aged 65-94 years) in control group, 28 with femoral neck fracture and 47 with intertrochanteric fracture of femur. In the prophylaxis group, comprehensive prophylaxis for DVT which included Aspirin, fibrinolytic enzyme, passive and active circumduction of the foot and ankle, CPM management wasappl ied. In the control group, no thromboproxylaxis was taken. All patients in the both groups received color doppler flow imaging (CDFI) examination before operation and on the 7th and 14th days after operation. Results CDFI found 2 cases of DVT in the prophylaxis group 7 and 14 days after operation respectively, while 21 and 15 cases of DVT in the control group respectively. The incidence of DVT was 48.0% in the control group compared with 4.9% in the prophylaxis group and the reduction was significant (P lt; 0.01). One patient gave up the intervention due to Melena 3 days after operation in the prophylaxis group. In the control group, 1 patient died 8 days after operation and another died 11 days after operation. Both died of acute pulmonary embol ism confirmed by autopsy. Conclusion The comprehensive prophylaxis can significantly decrease the incidence of DVT in geriatric patients after proximal femur fractures. There is no significant adverse effect during the intervention.