Abstarct: Protection of a structure, the human occupants and its material content, against damage induced by large environmental loads, e.g., earthquake, is without doubt, a serious chanllenge in the civil engineering. Inelastic deformation baxsed design methods have become a thing of the past and the focus is now on structural control. Classical control algorithms need an exact mathematical model for an actual structure to minimize its vibration. Today, structures that are built are more slender and flexible and contain complex features. Therefore, obtaining a reduced order model becomes erroneous and control mechanism baxsed on this approach never becomes optimal. Fuzzy logic baxsed control neither needs an accurate mathematical model nor does it depend on a reduced order model. In this study, fuzzy logic controller (FLC) designed for a multi-degree of freedom structure with a semi-active tuned mass damper (SATMD) to suppress earthquake-induced vibrations. SATMD uses a small amount of external power to modulate the damping. FLC is preferred because of its robust character and superior use effectively and easily in semi-active control. A ten degree of freedom model with a SATMD on the top floor of structure has been used. Semi-active MR damper used as a actuator. At the end of study responses of displacements, accelerations, SATMD displacements are presented. Performance of the designed FLC has been shown for the El Centro, Hachinohe, Northridge and Tabas earthquakes. Simulation results for SATMDs and its equivalent TMDs are compared.