In this study, the buckling restrained braces are reinforced with engineering plastics(EP-BRB) that can compensate for the disadvantages in the manufacturing process of the existing buckling restrained brace. Performance tests were conducted on a two-story full-scale frame test. The load-displacement curve showed stable hysteresis behavior without strength reduction within the target displacement. The strength of the reinforced specimen showed a significant increase at both LS(Life Safety) level and CP(Collapse Prevention) level. Notably, the maximum strength of the reinforced frame specimen was 4.33 times greater than that of the un-reinforced frame specimen. In the future, it will be essential to conduct structural performance tests that consider various experimental variables and research finite element analysis.