The invention discloses a cold-heat composite manufacturing method for machining of the hollow turbine blade inner cavity precision casting appearance. The method comprises the steps that a turbine blade casting blank model is designed, a blade blank is cast, and the blade six-freedom-degree positioning datum point or the blade equivalent structure of the six-freedom-degree positioning datum pointis reserved; a rapid replacement clamp tray or a measuring clamp is arranged on a blade rabbet part, and accurate positioning of the blade is conducted; an industrial CT measuring device is used forobtaining point cloud data of a blade inner cavity, the blade inner shape and appearance, other related surfaces, auxiliary positioning datum and the like, a coordinate system is designed after fitting, and grinding machining or milling machining is conducted on the auxiliary positioning datum on the blade and the blade body appearance; the blade is positioned and clamped according to the machinedblade body appearance, and a tenon grinding machine tool is utilized for machining a blade tenon and other end portion structures; and air film holes in the blade are machined through tenon positioning. The casting process is simplified, meanwhile, the blade inner cavity and appearance manufacturing precision is guaranteed, the strict requirement for precision of the relative position of the blade inner cavity and the blade appearance is guaranteed, and the hollow turbine blade manufacturing qualification rate can be obviously increased.