A rotary machine blade (31) equipped with a clearance flow suppression blade section (34), the lean angle of which has one or more inflection points, and which is formed such that when the direction from a positive-pressure surface (31a) to a negative-pressure surface (31b) is taken as the normal direction, an inflection point (P1) of the lean angle positioned farthest toward the blade end (33) changes from the negative to the positive direction in the direction away from the blade end (33).