Abstract : This paper takes a micro turbojet engine as the working object, uses an 8098 microcontroller as the digital controller, and a computer as the model engine. It specifically introduces the overview of the CNC semi-physical simulation test system, the establishment of the engine's mathematical model, the overall hardware design of the system, the adaptive model-following controller, and its software design. Based on this, a real-time CNC semi-physical simulation test system for the engine was established and tested. The results prove that the designed system can reflect the real test process under the control system in real time. Keywords : Micro turbojet engine; CNC system; Semi-physical simulation test 1 Introduction The digital control system of an aero-engine consists of actual sensors, circuit interfaces, actuators, controllers, and the controlled object (aero-engine). Any malfunction in any of these components can cause abnormal engine operation, and in severe cases, damage the engine. Therefore, conducting semi-physical simulation tests is an important part of developing an engine CNC system. Micro turbojet engines are often used as power plants for missiles and unmanned aerial vehicles. To ensure safe flight and maximize the performance of the engine under various environmental conditions, engine control is an essential component. The structural characteristics, working environment, and usage requirements of micro turbojet engines differ from those of large engines; therefore, the control system cannot simply copy the design of a large engine. FADEC (Full Authority Digital Electronic Control) relies on digital electronic technology to perform all necessary calculations and controls on the engine. It not only offers high control precision and fully utilizes the engine's performance potential but also features fault diagnosis and status monitoring functions, and its programs are easy to modify and maintain. Designing a real-time semi-physical simulation system for CNC to simulate a real engine for testing can verify the feasibility of the control system and provide a reference for further system design. It significantly reduces the risks during actual testing while minimizing time and cost, making it extremely important in the development of CNC systems. This article mainly introduces the design and testing of a real-time semi-physical CNC system for a micro turbojet engine. [b][align=center]For details, please click: Real-time Semi-Physical Simulation Test System for Digital Control of Micro Turbojet Engine[/align][/b]