A steam turbine includes a bucket implanted in a turbine rotor and a nozzle disposed on an upstream side of the bucket and supported by a turbine casing, in which a plurality of stages, each including the bucket and the nozzle, are arranged axially in the turbine so as to define a steam path. A hydrophilic coating portion is disposed in the entire area or an area of at least one portion of a circumferential surface of the turbine rotor, surfaces of the nozzles, surfaces of the buckets, and an inner circumferential surface of the turbine casing.