This gas turbine blade comprises a platform part having a cooling passage formed inside, and a wing body part protruding from the upper surface of the platform part. A plurality of first ejection ports that eject a gas supplied from the cooling passage are formed in an inner chordal region of the upper surface, which is positioned further toward the wing-body side than a wing chord connecting the leading edge and the trailing edge of the wing body part. A plurality of second ejection ports that eject the gas supplied from the cooling passage are formed in an outer chordal region of the upper surface, which is positioned on the side opposite the inner chordal region with respect to the wing chord. The outer chordal region has an outer chordal leading edge region positioned on the leading-edge side and an outer chordal trailing edge region positioned on the trailing-edge side, more second ejection ports being formed in the outer chordal leading edge region than in the outer chordal trailing edge region.