The invention discloses a topology structure used for a multi-level T-shaped converter, which can achieve rectifier conversion and is characterized in that the longitudinal axis of the T-shaped converter consists of 2k capacitors such as CT1, CT2, and to CTk-1, CTk, CB1, CB2, and to CBk-1 and CBk; the transverse axis of the T-shaped converter consists of k bidirectional controllable switch such as S1, S2, and to Sk-1 and Sk; a branch is arranged between nodes Di of Si and Si+1 (i is equal to 1, 2, and to k-1) and nodes DTi of CTi and CTi+1 (i is equal to 1, 2, and to k-1); a unidirectional rectifier branch flowing from the transverse axis to the longitudinal axis consists of STk1, STk2, and to STk2k; another branch is arranged between the nodes Di, CBi>and CBi+1 (i is equal to 1, 2, and to k-1); the branch is a unidirectional rectifier branch which flows from the longitudinal axis to the transverse axis and consists of SBk1, SBk2, and to SBk2k, with the direction reverse to the previous branch; one end of the bidirectional controllable switch S1 is connected with the middle point of the longitudinal axis capacitor. Number of levels can be increased by extending switch tubes, capacitors and rectifier branches; single-phase circuit combination can be applied to multi-phase systems. The topology structure can easily improve the number of levels of the converter and overcome the shortages that the capacitor of the prior art has non-uniform voltage and large quantity of devices.