In this paper, we study skew-cyclic codes over the ring S = Z 8 + uZ 8 + vZ 8 , where u 2 = u, v 2 = v, uv = vu = 0. We consider these codes as left S [x, θ]-submodules and use Gray map on S to obtain their Z 8 -images. The generator and parity-check matrices of a free θ-cyclic code of even length over S are determined. Also, these codes are generalized to double skew-cyclic codes. We give some examples using Magma computational algebra system.