The invention discloses an L-shaped antenna array low computation complexity two-dimensional DOA (Direction of Arrival) estimation method, mainly solving the problems of high computation complexity and poor estimation performance under a low signal to noise ratio and small snapshots of a present L-shaped antenna array low computation complexity two-dimensional DOA estimation method. The method comprises the steps of: (1) receiving signals; (2) constructing a cross-correlation matrix; (3) constructing an orientation augmentation matrix; (4) constructing a pitching augmentation matrix; (5) estimating an azimuth; (6) estimating a pitch angle; and (7) paring two-dimensional angles. The method utilizes an ESPRIT (estimation of signal parameters via rotation invariant technique) algorithm and a diagonal Toeplitz matrix to decompose characteristic values, realizes L-shaped antenna array DOA estimation with low computation complexity, a low signal to noise ratio and small snapshots, and can be used for radar and communication target location.