A molding machine for making thermoplastic composites contains: a machine frame, a platform, a heating device, a vacuum means, and a gas barrier film. The machine frame includes a working stage. The platform is mounted on the working stage and includes channels, a curved pattern portion and plural tiny holes which are arranged on the top surface of the platform, wherein the plurality of tiny holes communicate with the channels. The platform also includes a connector fixed on one side thereof and communicating with the channels. The heating device is secured on a bottom end of the platform and heats a working material on the platform. The vacuum means is arranged in the machine frame and includes a pipe for coupling with the connector. The gas barrier film is flaky and covers the top surface of the platform.