This paper describes an outdoor positioning system that can be applied for an urban canyon by using an omni-directional IR camera and the DSM (Digital Surface Model). The image captured by an ER camera has high robustness to light disturbances in the outdoor environment. The omni-directional image, which includes several building profiles, is compared with building-restoration images that are calculated from the corresponding DSM in order to identify the self-position. Field experiments at Fujisawa City show that the proposed outdoor positioning method is valid and effective even if high-rise buildings cause satellite blockages affecting GPS measurements.