A novel Toeplitz fourth-order cumulantsorthonormal propagator rooting method to direction-of-arrivalestimation for uniform linear arrayis addressed in this paper. Specifically, the modified (reduced-dimension)matrix is achieved at first via removing the redundant information encompassed in the primarymatrix, and then thematrix which possesses Toepltiz structure can be recovered by utilizing the Toepltiz approximation method. To reduce computational complexity, we adopt an effective method which depends on the polynomial rooting technology. Finally, the DOAs of incident signals can be estimated by exploiting orthonormal propagator rooting method. The theoretical analysis coupled with simulation results show that the proposed resultant algorithm can reduce computational complexity significantly, as well as improve the estimation performance in both spatially-white noise and spatially-color noise environments.