The invention provides an aircraft structure dead angle anti-corrosion design method. The aircraft structure dead angle anti-corrosion design method comprises the following steps that a nonabsorbent material is processed into a filling cushion block (1), and the shape of the filling cushion block (1) is the same as the structure shape of a filling area (2) in an aircraft structure dead angle; surface protection treatment is conducted on the filling cushion block (1); the filling cushion block (1) is fixedly installed in the filling area (2), and a gap between the filling area (2) and the filling cushion block (1) is filled with a sealant (3); the surface of the filling cushion block (1) is sealed with a wrapping layer; and a non-filling area in the aircraft structure dead angle is provided with a drain hole (4) used for draining accumulated water and accumulated liquid. According to the aircraft structure dead angle anti-corrosion design method, the structure weight can be reduced; the structure dead angle area anti-corrosion performance is improved; the structure service life is ensured; and in addition, assembling and disassembling are convenient.