The invention provides a root value MUSIC-based mixed structure-based angle of arrival estimation method in a large-scale MIMO system. According to the method, analog beamforming and digital beamforming are combined, analog beamforming design is performed by using a phase shift network, a digital beamforming vector is designed by using a root value MUSIC algorithm, so that an angle of arrival of an arrival wave signal is estimated by using a direction ensuring highest receiving power. As the antenna array grows largely, in digital beamformign, each antenna needs a dedicated radio frequency (RF) link, while, mixed beamforming can remarkably reduce RF links so as to remarkably lower hardware cost. Compared with analog beamforming, mixed beamforming may improve the performance remarkably dueto introduction of digital beamforming. The mixed beamforming algorithm considers both the large-scale MIMO system performance and hardware cost, estimates the angle of arrival of the arrival wave signal effectively, and makes angle estimation less complex.