The control system of a micro turbine engine plays a crucial role during engine operation. This paper focuses on the design of a speed control system for a specific micro turbine engine. Starting from the overall architecture, the control structure of the system is designed. A speed control law design method based on Linear Active Disturbance Rejection Control (LADRC) technology is proposed. Subsequently, research is conducted on hardware implementation and software development using the STM32F103VET6 embedded microprocessor to develop the hardware controller for engine speed control. Addressing the potential issue of direct conduction in the half-bridge fuel pump drive circuit, a delay circuit is designed to control the conduction time of MOSFET. A three-layer software architecture is utilized for the design, development, and debugging of programs for speed measurement, closed-loop control, and other functions. Finally, a speed control system experimental verification platform is constructed to test and validate the fuel pump drive circuit, delay circuit, and speed control system. Experimental results demonstrate that the drive circuit exhibits stable and reliable on-off characteristics. The engine speed can rapidly follow the target speed, with a steady-state error of less than 1%, meeting the application requirements of the micro turbine engine control system.