The invention discloses a disc-type built-in aero starter generator, which belongs to the field of aero engineering. The disc-type built-in aero starter generator comprises a high-voltage shaft, a first stator iron core, a rotor iron core, first armature coils and a second stator iron core, and is characterized in that the rotor iron core is fixed on the high-voltage shaft of the aero engine; thefirst stator iron core and the second stator iron core with the same structures are symmetrically located at two axial sides of the rotor iron core and are fixed on the shell of the aero engine; 3k fan-shaped through holes are distributed uniformly on the circumference of the rotor iron core, and k is a positive integer larger than 1; and one side, facing the rotor iron core, of each of the firststator iron core and the second stator iron core is provided with 4k uniformly-distributed fan-shaped convex armature poles, and the armature poles of the first stator iron core are wound with integrated armature coils. The rotor iron core in the invention has small moment of inertia, and high-speed rotation can be achieved; and the rotor iron core is located on the high-voltage shaft of the engine, the rotation speed is high, the power is larger, and the disc-type built-in aero starter generator is extremely suitable for serving as an aero built-in generator.