The propose of this study is to evaluate the width-thickness ratio of the HSB800 steel beams satisfying the rotation demand (R) required for compact section. To investigate the properties of HSB800, coupon tests were conducted, from which HSB800 has the three properties - high yield ratio, low strain-hardening ratio, and small strain capacity. The rotation capacity of the HSB800 steel beams are evaluated using finite element analysis (FEA). From the FEA results, the rotation capacity (R>3) of HSB800 steel beams do not satisfy the limiting value specified in current code. Based on the experiment and theories, this study propose a limiting value of the width-thickness ratio of HSB800 for R>3.