The invention provides a cooling turbine blade (A1) for a minitype gas turbine engine, which comprises a cooling channel (12) formed in the cooling blade (1), through which air coolant flows; film cooling holes (13) which penetrate through the surface of an inner wall (111) and the surface of an outer wall to form a cooling film; an impingement cooling component (2) provided with a plurality of pinholes (21) to spray air coolant out. A hermetic unit (14) is arranged on an interval t formed by the surface of the inner wall (111) and the impingement cooling component (2), and divides the interval in the direction of the chord of the blade.