Abstract： Objective Delve into the applied value of CDFI to diagnose deep vein thrombosis(DVT)in lower limbs.Methods Analyze the diagnosis of 65 chronic cases of DVT with a two-dimensional CDFI,and contrast it with the operation,X-ray angiography and clinical features.Results 36 acute cases of DVT;29 chronic cases of DVT;38 cases of lesion in left lower hmb(58.5%);21 in right lower limb(32.3%);and 6 in both lower limbs(9.2%).In the chronic cases,11 have formed collateral branch circulation.Conclusion CDFI has a safe and rapid effect on vein illness in lower limbs and can show the state of blood streams and the condition around the veins.It Can explain the unknown swollen in limbs.Realizing DVT in early stage has good value for its occurring,expanding and treating.