The invention discloses a three-level three-phase unbalance correction device and correction method capable of generating phase change. The device comprises a hybrid three-level topological structure;the hybrid three-level topological structure comprises an I-type three-level bridge arm and a T-type three-level bridge arm; and an output side of each bridge arm of the I-type three-level bridge armand the T-type three-level bridge arm is connected to three phases through a relay for selecting the I-type three-level bridge arm or the T-type three-level bridge arm for the three phases through the relay. The method comprises the following steps: respectively selecting the I-type three-level bridge arm or the T-type three-level bridge arm for the three phases according to the load current levels of the three phases. By adoption of the three-level three-phase unbalance correction device and correction method capable of generating phase change provided by the invention, the combination sequence of the three phases can be adjusted online to better adapt to the three-phase load conditions which changes in real time and to reduce the conduction loss.