Objective:To observe the clinical efficacy of Tengtong Formula with external application in the treatment of acute soft tissue injury after type B ankle fracture (AO classification). Methods60 patients with type B ankle fracture were randomly divided into the Voltaren group and Tengtong Formula group,30 cases in each group. Both groups were treated with conventional measures including lifting affected limbs,stopping activities and immobilization. Meanwhile the Voltaren group was treated with Votalin Emulgel(diclofenac diethylamine emulgel)by external application,and the Tengtong Formula group was treated with Tengtong Formula by external application. Before treatment,24 and 48 hours after injury,the limb circumference difference of affected limb,visual analogue scale(VAS)score,serum trauma indicator creatine kinase(CK),serum inflammation indicators including C-reactive protein(CRP) and interleukin-6(IL-6)were determined,and the adverse events(skin allergy,incisional infection,incision delayed union)were observed during follow-up.  Results:①In the Voltaren group,the limb circumference difference was increased progressively during 48 hours after injury. In the Tengtong Formula group,the limb circumference difference was up to peak at 24 h and was significantly decreased at 48 h after injury,and the limb circumference difference at 48 h was lower than that at 24 h or before treatment(P<0.05). 48 hours after injury,the limb circumference difference in the Tengtong Formula group was also significantly lower than that in the Voltaren group(P<0.05). There was definite analgesic effect in the Voltaren group and Tengtong Formula group,with no statistical difference(P>0.05). ②There were no statistically significant differences on serum CK level among each observation timepoint in the Voltaren group(P>0.05)；while in the Tengtong Formula group,the serum CK level at 48 h was significantly lower than that at 24 h or before treatment(P<0.05). Compared with treatment before,the levels of CRP and IL-6 were significantly increased at 24 h and 48 h in the Voltaren group(P<0.05),and the levels of CRP and IL-6 were significantly decreased at 48 h in the Tengtong Formula group(P<0.05). 48 hours after injury,the levels of CRP and IL-6 in the Tengtong Formula group were significantly lower than those in the Voltaren group(P<0.05). ③There was no statistically significant difference on the incidence of adverse events between the two groups(P>0.05).  Conclusion:Tengtong Formula can effectively reduce the pain and limb swelling of patients with acute soft tissue injury after type B ankle fracture,improve the serum trauma and inflammation indicators. Its effects of relieving swelling and suppressing inflammation are better than that of Votalin Emulgel,with no obvious increasing on incidence of adverse events.