As the skylight polarization navigation at present is based on dead reckoning which can only provide orientation information to navigate but not the geographic position of the observer, an autonomous positioning method based on skylight polarization, and the relative relationship between the earth and the sun was proposed by the author through the previous work. An experiment platform which consists of a three-camera skylight polarization angle measuring module, an OCTANS INS module and an ephemeris inquiring module are presented, as well as a basic verification experiment of the autonomous positioning method is carried out. The experiment result shows that the positioning system is able to provide a relative reliable longitude and latitude of the vehicle real-time, which validates the feasibility of the positioning method. Although the experiment platform provides a latitude error of 0.418° and a longitude error of -0.149° in average which is larger than GPS, it still could be a back-up positioning system when the GPS signal is out of service.