The invention aims at providing a single-shaft and double-compressor controllable supercharger structure which comprises a turbine, a compressor A and a compressor B. An inlet air channel of the turbine communicates with an exhaust pipeline of an engine, and an outlet air channel of the turbine communicates with the atmosphere. An outlet air channel I of the compressor A communicates with an intake pipeline of the engine. The turbine is coaxial with the compressor A. The compressor B communicates with a shaft of the compressor A through a coupler which can be controlled to be disconnected or connected with the compressor B. An inlet of the compressor B is connected with an inlet air channel II which communicates with the atmosphere. An outlet of the compressor B is connected with a communication air channel II. An inlet of the compressor A is connected with a communication air channel I. An inlet air channel II of the compressor A, the communication air channel I and the communication air channel II are connected through a switching control valve with a tee joint function. The inlet air channel I communicates with the atmosphere. According to the single-shaft and double-compressor controllable supercharger structure, switching of single-stage supercharging and two-stage supercharging can be achieved, the structure size of a supercharging system is obviously reduced, the supercharger structure is reasonably matched with an internal combustion engine under wide work conditions, and therefore a supercharger can run in a high-efficiency area.