A turbine blade includes an airfoil body, and a plurality of cooling passages extending along a blade height direction inside the airfoil body and being in communication with each other to define a serpentine flow passage. The plurality of cooling passages include first turbulators on an inner wall surface of an upstream cooling passage of the plurality of cooling passages, and second turbulators on an inner wall surface of a downstream cooling passage of the plurality of cooling passages. A second angle formed by the second turbulators with respect to a flow direction of a cooling fluid in the downstream cooling passage is smaller than a first angle formed by the first turbulators with respect to the flow direction of the cooling fluid in the upstream cooling passage.