For reducing the complexity of non-circular signal, the paper proposes a computationally efficient direction-of-arrival (DOA) estimation algorithm for noncircular signals. Firstly, the array extension matrix is constructed and the covariance matrix is formed by the characteristics of non-circular signal. Secondly, the noise subspace is achieved by using the extended propagator method without the eigendecomposition of the covariance matrix. Thirdly, the estimating value of DOA is obtained by the polynomial rooting method based on uniform linear arrays. The simulation results indicate that the performances of the algorithm are close to those of NC-root-MUSIC, NC-ESPRIT and NC-MSWF- MUSIC. The analysis of the complexity show that the proposed algorithm is computationally efficient in comparison to the above mentioned algorithms without complex computation and also demonstrate the rapid and effective performances of the proposed algorithm.