In this paper, we have evaluated the L1 submeter-class augmentation with integrity function (L1-SAIF) broadcasted by the Quasi-Zenith Satellite System (QZSS) in an urban environment for vehicle positioning. In urban environments, the augmentation of QZSS can be expected to be fairly effective because of the high elevation angles. Therefore, we conducted static and kinematic evaluation tests to verify thus. In the static evaluation test, for evaluating the positioning accuracy, we compared the positioning errors for only GPS positioning and augmentation of QZSS positioning. In the kinematic evaluation test, for evaluating the availability, we compared the visibility of QZSS and SBAS satellites. From the evaluation tests, it was confirmed that the QZSS augmentation has better availability and effectiveness than the SBAS augmentation. © 2011 SICE.