The ductility and strength properties of lightweight steel brace element for structural strengthening of unreinforced masonry (URM) wall is reported in this study. The performance of URM wall without brace and with brace is evaluated by an elastoplastic nonlinear analysis including the yield criterion, flow rule and hardening rule. Masonry constituent is implemented into two-dimensional finite element model developed in Fortran code. The brittle failure of URM wall is analyzed using by an interface element to model bricks and joints. Two types of steel brace elements which can resist only tension and both tension and compression have been considered to increase the ductility of URM wall. The comparison between experimental and numerical results adopted in simplified-micro masonry modeling is illustrated with the relationship between force and displacement. The ductility and strength of masonry wall with the tension and the tension-compression brace element were different results of URM wall by in-plane pushover analysis. As for the simplification for a calculation of masonry wall, equivalent masonry model is discussed and besides diagonal brace elements, the additional vertical brace element is assumed for the high masonry wall by the numerical analysis.