In this paper, we study the influence of Platinum (100) surface morphology on the Tangential Momentum Accommodation Coefficient (TMAC) with Argon usingMolecular Dynamics method (MD). The coefficient is computed directly by beaming Ar atoms into the surfaces and measuring the relative momentum changes. The wall is maintained at a constant temper-ature and its interaction with the gas atoms is governed by the Kulginov potential [1]. To capture correctly the surface effect of the walls and atoms trajectory, the Quantum Sutton-Chen multi-body potential is employed between the Pt atoms [2]. Effects of wall surface morphology and incident direction, temperature are considered in this work and provide full information of gas-wall interaction.