The invention relates to the technical field of array signal processing technology, especially relates to DOA (Direction Of Arrival) estimation of a wireless signal source, and particularly relates toa uniform circular array differential phase based single distributed source DOA estimation method. The method includes calculating a corresponding covariance matrix through output signals of different array elements of the uniform circular array; extracting exact upper triangular element phases of the covariance matrix and performing vectorization treatment, and obtaining a differential phase vector; obtaining single distributed source central azimuth angle estimation and central pitch angle estimation through least squares estimation. According to the invention, a two-dimensional DOA closed-form solution is obtained directly through the least squares method, spectrum peak search and eigenvalue decomposition calculation are avoided and complexity is reduced substantially.