Urban area can be considered as an assembly of various shapes and sizes of urban canyon. The climate of urban canyon is primarily controlled by micrometeorological effects of canyon geometry, though it is also affected the mesoscale phenomenon in urban boundary layer. This study presents an analysis of the air flow characteristics for urban canyon, based on three dimensional wind components data which are measured with four ultra-sonic anemometers mounted along pedestrian bridge The summary is as follows : 1) The strong circulation flow is derived from southerly sea-breeze during daytime and counter-circulation flow corresponding to land-breeze is also apparent in the early morining. 2) As for the parallel component to the street, its direction changes due to the deflection of upper wind direction from right angle to the street.
