The invention belongs to the field of material additive manufacturing and the field of 3D printing and particularly relates to a diffusion-bonding-based metal structure member material additive and subtractive composite manufacturing method in order to solve the problems that complex structure manufacturing is limited, raw materials are wasted seriously, the machining efficiency is low, the material additive manufacturing process equipment is high in cost input, the requirements for raw materials are harsh and the product precision and performance are poor by means of a traditional process. The method comprises the steps of (1) establishing a three-dimensional CAD graph according to a metal structure member and conducting slicing machining on the three-dimensional CAD graph; (2) machining a metal plate into lamina parts; (3) removing metal oxide films; (4) conducting stacking and positioning; and (5) conducting diffusion connection to obtain a metal structure member. By means of the method, the problems that the complex structure is limited, raw materials are wasted seriously, the machining period is long, the energy consumption and cost input are high, the applicability of raw materials is limited and the product precision and performance are poor by means of a traditional metal structure member machining process are solved.