To reduce leaked flow quantities of hot gas flow with respect to a prescribed pressure difference along the whole of a blade end part by arranging an offset squealer on an inner side from an outer periphery of a rotary blade, in a blade end cap of a blade end part of the rotary blade.

A rotor blade part consists of a root part and an aerofoil of an inner side and a blade end part 20 of an outer side, and the blade end part 20 is sectioned by pressure and suction side walls 22, 24, front and rear edges 26, 28, and a blade end cap 30. In the blade end part cap 30, an offset squealer 50 is disposed on an inner side from an outer periphery 52 of the blade end cap 30. In the offset squealer 50, a tip end shaped rim, and a fence or seal belt plate are formed, which are protruded inward the blade end cap 30, and a step 54 or a rack is formed on all circumference of the blade and cap 30. An ejector fluid resistance is formed on a clearance gap between the blade end part 20 and an outside shroud, and thereby, leakage flow between the blade end part 20 and the shroud is weakened and deflected.