In this paper, a new technique to solve a mathematical model of thin film flow of third- grade fluid in an inclined plane is presented. This technique is based on combining the homotopy perturbation method with the Laplace transform and Pade´ approximation approach. The results we obtained showed that the proposed technique has high accuracy than other classical methods to solve this model. The measurements of error are tabulated. the validity and usefulness of the new method are derived. Moreover, the influence of parameters on the velocity profile is discussed graphically.