In this article we emphasize on the powerful of the residual power series method (RPSM) as analytical and numerical method that has been successfully applied on the fractional gas differential equations. The effectiveness of this method is shown by finding analytically the exact solution of the nonlinear homogeneous and nonhomogeneous fractional gas differential equations. The time-fractional derivative is considered in Caputo sense. The Numerical computations and graphs for the integer and fractional gas differential equations Using Mathematica package. Results interrupt the powerful and efficiency of the series solution using (RPSM) and show how this method is significant in the world of fractional differential equations.