The invention provides a turbine blade. The turbine blade comprises a blade body, wherein the blade body is provided with a blade tip and a blade root, a blade tip plane is formed on the blade tip onthe top end of the blade body, a concave cavity is formed in the turbine blade, the concave cavity is in a streamline shape, an opening is formed in the concave cavity, the opening is located in the blade tip plane, and the part of the concave cavity along with the cross section of the turbine blade is formed by a plurality of sections of arcs.