To explore the effects of Tongmai Decoction on deep venous thrombosis and its thromboelastogram in closed fracture of lower extremity，so as to select the best treatment method and improve the curative effect.Methods:A total of 92 patients with deep venous thrombosis(DVT)of closed limb fractures admitted to Affiliated Hospital of North Sichuan Medical College from December 2016 to May 2018 were randomly divided into a control group(46 cases)and an observation group(46 cases)according to the order of treatment.The control group was treated with conventional western medicine，while the observation group was treated with Tongmai Decoction.All patients were treated with 10 d.The levels of PECAM-1，VCAM-1，D-dimer，P-selectin and fibrinogen(FIB)were observed before and after treatment in the 2 groups.The whole blood high shear viscosity，whole blood low viscosity plasma specific viscosity，and blood coagulation factor I before and after treatment were compared.The edema，pain，skin color abnormalities，skin temperature abnormal integral changes before and after treatment were observed.The thrombus elasto graph before and after treatment was compared.The adverse reactions were observed and calculated during the treatment.Results:There was no significant difference in PECAM-1，VCAM-1，D-D，P-selectin and FIB between the 2 groups before treatment(P>005).After treatment，the above indexes in both groups were significantly decreased than those before treatment(P<005).After treatment，the above indexes in the observation group were significantly lower than those in the control group(P<005). 2)There was no significant difference between the 2 groups in the whole blood specific high shear viscosity，whole blood specific low shear viscosity，plasma specific viscosity and coagulation factor I before treatment(P>005).After treatment，the above indexes in both groups were significantly decreased than those before treatment(P<005).After treatment，the above indexes in the observation group were significantly lower than those in the control group(P<005). 3)There was no significant difference in edema，pain，skin color abnormality and skin temperature between the 2 groups before treatment(P>005).After treatment，the above indexes in both groups were significantly decreased than those before treatment(P<005).After treatment，the above indexes in the observation group were significantly lower than those in the control group(P<005). 4)There was no significant difference in R value，K value，MA value and a angle between the 2 groups before treatment(P>005).After treatment，R value and K value increased significantly，and MA value and a angle decreased significantly(P<005).After treatment，the above indexes in the observation group were significantly better than those in the control group(P<005).There was no significant difference in gastrointestinal reactions，allergic reactions，abnormal liver and kidney functions，and the incidence of bleeding between the 2 groups(P<005).Conclusion:Tongmai Decoction can promote the blood circulation of DVT in closed fracture of lower limbs，improve blood viscosity，improve symptoms and improve curative effect.