Disclosed herein is a turbine blade having a leading edge, a trailing edge, a pressure side, and a suction side and having a cooling passage formed therein. The turbine blade includes a plurality of cooling holes formed on the pressure side or the suction side. Each of the cooling holes includes, a through-hole having a circular cross-section and angled outwardly toward the pressure side or the suction side from the cooling passage, a circular sink formed concavely with respect to the pressure side or the suction side in the vicinity of an upstream side of an exit of the through-hole, and an elliptical sink formed concavely with respect to the pressure side or the suction side in the vicinity of a downstream side of the exit of the through-hole.