The race toward new heights has led to the construction of tall flexible buildings with low inherent structural damping. As buildings get taller their sensitivity to wind excitations increases which threaten their integrity and serviceability. Therefore the control of gust responses of tall buildings has gained worldwide attention. In this work an adaptive Sliding Mode Control (SMC) driven Magneto Rheological (MR) fluid damper is proposed for the vibration control problem of a wind excited tall building. The equivalent control part proposed in this work is based on filtering the overall discontinuous control signal for a better satisfaction of the reachability condition on one hand, and to heal the chattering phenomenon on the other which is further reduced by replacing the hard switching sign function by the sigmoid-like function. The adaptive tactic is based on using 3 second time average variations of the gust speed to estimate the wind loading on the structure by utilizing the theory of quasi-steady aerodynamics.