Stability and reliability are the essential properties for the control system of the no stroboscopic medical shadowless lamp. This paper designs an intelligent control system based on STM32F103 for medical shadowless lamp. PWM (Pulse Width Modulation) control technique is utilized to realize the no stroboscopic work and rapid multistep regulation. By detecting the working condition of shadowless lamp in real time, it's convenient to switch between the main and vice lamps. Test result shows that the designed control system are both stable and reliable, meeting the related requirements of the medical shadowless lamp.