Variety of cooling techniques are being applied in gas turbine, due to gas turbines operated at high temperature. The coolant used for cooling uses compressed gas in the compressor. Thus, excessive cooling can lead to system efficiency loss. Therefore, for effective cooling, it is necessary to understand the internal environment of the actual gas turbine. In this study, we will analyze the heat transfer characteristics of endwall with wake in front of blades through numerical analysis. In order to make a wake, rods are placed in front of the blade, and the heat transfer characteristic according to the position change of the rod is examined. Numerical analysis was conducted through DES. A wake from a rod changes the vortex structure present in the endwall. Therefore, the heat transfer distribution in the endwall also changes.