In order to improve the stress lag problem when using orthogonal steel strips to strengthen brick masonry walls，it is proposed to apply pre-tension stress to horizontal steel strips. Five specimens were tested under low reversed cyclic loading. The failure process of the specimen was described，and the hysteretic curve，skeleton curve，bearing capacity，stiffness and ductility were also analyzed. The results show that strengthening brick masonry wall by pre-stressed steel strips can improve its seismic performance; increasing the steel strips’ pre-stress level within the appropriate range can further improve the bearing capacity of the specimen，and has little effect on the lateral stiffness corresponding to its cracking point，but the ductility decreases slightly; increasing the Vertical load level of the wall can improve both the bearing capacity and lateral stiffness of the specimen，but the ductility also decreases slightly; and increasing the aspect ratio of the wall to 1，the strengthening effect is relatively worse. Furthermore，based on the analysis of the strain development of steel strips，it can be found that pre-stress application can effectively improve the utilization ratio of the material. Finally，the recommended value of pre-stress and calculating formula of shear capacity were proposed.