Particle image velocimetry (PIV) was applied to the turbulent flow within and above an outdoor urban scale model. The setup of the PIV system and the preliminary results were presented. Two dimensional turbulent flow fields in a vertical cross section of street canyon (3 x 3 m) were measured continuously for 60 min; the spatial and temporal resolutions were 5cm and 1/30 sec, respectively. The mean wind vector and turbulent statistics were successfully obtained. Also the PIV results were validated with measurements of ultrasonic anemometer which is conventional instrument for the investigation of atmospheric turbulence. Most of them showed good agreements within the error of 10% although the data aquisition ratio was still low.