Abstract: With the validation of wind-tunnel test, the wind speed was investigated by CFD simulation with RNS model using enhanced wall treatment wall function under different wall heating conditions in street canyon. The results revealed that wall heating have significant impact on wind velocity in the canyon. Whole wall heating exerted greater influence on wind velocity than linearly heating. Windward wall heating decreased wind velocity and leeward wall heating increased wind speed in the canyon. The work also indicated that thermal buoyancy could improve pedestrian-level ventilation to a certain extent. The result would provide a meaningful reference for urban planning.