Aiming at the problem that the attitude sensor of the quadrotor was susceptible to interference, resulting in large attitude output errors, a multi-sensor quadrotor attitude control system based on STM32 was designed. The system used sensors such as MPU6050 to collect the attitude data of the quadrotor in real time, calculated the attitude through the quaternion complementary filtering algorithm, and used the cascade PID control to drive the motors in PWM mode. Based on the design of the software and hardware of the system, the physical production and flight test of the quadrotor were completed. The results show that the system can flexibly control the attitude of the quadrotor UAV and realize the stable flight of the quadrotor UAV.