Abstract: The difficulty of adaptive reclosure technology for transmission line lies in the accurate identification of fault characteristics. Aiming at the scenario of fault on the line equipped with unified power flow controller（UPFC）, a three-phase adaptive reclosure scheme based on characteristic voltage injection is proposed by using the flexible controllability of UPFC.Firstly, by switching the control mode of modular multilevel converter（MMC） on the series side of UPFC, the injection characteristic voltage is controlled by constant U/f. On this basis, permanent fault and transient fault are identified by judging whether the characteristic current is generated on the line. For the special scenario with high resistance fault, the staged injection characteristic current criterion is further proposed to improve the reliability of fault characteristic identification. Finally, the feasibility and effectiveness of the proposed scheme are verified by PSCAD/EMTDC simulation platform.