Abstract: A two-dimensional direction of arrival estimation method is proposed for three-parallel uniform linear arrays based on improved propagator method. Considering the geometric characteristic of the three-parallel ULAs, we obtain the rotational matrices by constructing an extended propagator matrix respectively for two vertical two-parallel ULAs of the three-parallel ULAs. Then the rotational matrices are paired by utilizing the feature of the three-parallel ULAs. Finally, the azimuth and elevation are jointly estimated by the paired rotational matrices. The proposed method has no estimation failure when the elevation angles are between 70° and 90°, and it makes full use of the elements, which improves the angle estimation performance with lower complexity. Simulation results demonstrate the effectiveness of the proposed algorithm.