The annular connecting straight cylinder engine has many advantages such as high power density, low inertia force and so on. However, the cylinder rotors always rotate along the circumferential direction of the output shaft during operation, which makes the traditional static gas distribution method no longer applicable. Therefore, it is of great significance to research and design a new type of gas distribution system that meets the intake and exhaust requirements of this type of engine. In view of the unique annular connecting structure and differential velocity motion characteristic of the engine, the volume change law of each rotor cylinder was analyzed, and the relationship between the intake and exhaust phases of each rotor cylinder and the rotor rotation angle was studied. On this basis, an innovative dynamic position gas distribution system with airway reuse feature was designed. According to the gas distribution scheme of two-stroke engine, the parts of the gas distribution system were designed and processed, and the dynamic intake and exhaust process was completed through high-pressure pneumatic test. The experimental results show that the engine can run stably at 200 r/min when the driving air pressure is 0.25 MPa, which effectively verifies the feasibility of the gas distribution system.