A blade (50) has a blade, passage (71) extending in a blade height direction (Dwh), a platform passage (81) formed inside a platform (60), and a communication passage (75) leading from an outer surface (93) of a shaft-mounted part (90) through the platform passage (81) to the blade passage (71). An inner surface defining an inflow passage portion (82) of the platform passage (81) includes a shaft-side inner surface (88) that faces a gas path side. The shaft-side inner surface (88) spreads in a direction having more of a component of a blade thickness direction (Dwt) than a component of the blade height direction (Dwh). An inner surface defining the communication passage (75) joins to the shaft-side inner surface (88).