Abstract: By using two variables (G′/G,1/G)function expansion method, and with the help of scientific computing software Mathematica, we obtained exact traveling wave solutions of hyperbolic function form, trigonometric form, rational function form for the timespace fractional nonlinear Kuramoto-Sivashinsky  equation. The results show that the (G′/G,1/G)function expansion method is simple and effctive, and is suitable for solving exact traveling wave solutions of other fractional nonlinear partial differential equations.

Key words: timespace fractional KuramotoSivashinsky equation, exact traveling wave solution, (G′/G,1/G)function expension , method