The invention discloses an optimal solar panel mounting angle measuring system which comprises a single chip microcomputer, a control circuit module, an omnibearing rotating cradle head, a solar panel, a Bluetooth wireless sending module, a computer and maximum average power algorithm software. The solar panel is mounted on the omnibearing rotating cradle head. The measuring system is characterized in that the single chip microcomputer controls the omnibearing rotating cradle head to rotate and output power collection of the solar panel through a control circuit, rotation of the cradle head is controlled by adopting a mode combining horizontal rotating with vertical rotating, collected data are sent to the computer through the Bluetooth wireless sending module, and the computer performs data processing and analyzing through the maximum average power software which is designed to acquire an optimal mounting azimuth angle and an optimal mounting inclination angle. The two optimal angles including the azimuth angle and the inclination angle in mounting of the solar panel are directly acquired by adopting a method of field measuring, acquired results are more accurate, and the optimal solar panel mounting angle measuring system is of great value to photovoltaic arrays and meteorological studying.