This research investigated how the physical and chemical properties of Pt/TiO2-based catalysts with high activity in SCR reaction are affected by the preparation conditions (type of TiO2, Pt content and calcination temperature) using XRD, BET and TPR analysis. The catalyst preparation conditions that achieve optimumreactivity were identified by examination of how the physical and chemical properties relate to catalytic activity. According to the results, Pt content over 2 wt% causes a phenomenon in which Pt agglomeration increases linearly according to the surface area of the limited support. However, Pt content over 3 wt% showed an increase in reducibility in the low temperature region that is proportional to the absolute amount of Pt has increased. Moreover, although increased calcination temperature did not result in phase transition of the TiO2 support, it did lead to reduction of the surface area by increasing crystallinity and sintering of Pt.