The development of an attitude and heading reference system (AHRS) using sensor fusion is presented in this paper. The system consists of a nine degree of freedom inertial measurement unit (IMU) and a digital signal processor (DSP) module. The IMU comprises with triaxial gyroscopes, triaxial accelerometers, and triaxial magnetometers. By using the complementary filter, gain-scheduled complementary filter, and Kalman filter, the sensor fusion algorithms are implemented for the AHRS system. To verify the performance of the developed system, an experimental testbed of three-axis rotating platform is designed and constructed for experimental studies. It is shown that the robust performance can be obtained even though the system is in a dynamic state in the presence of a strong acceleration.