Bond characteristics have been investigated of cylindrical specimens with epoxy coated and uncoated bars under different ambient conditions. Forty six pull-out test carried cut on cylindrical specimens of 15 cm diameter and 30cm height with mild steel and deformed tensile steel bars. some of them were tested after exposed to temperature between 50 and 400O. Thickness of the epoxy coating film and grade of both concrete and steel were taken as variables. The results showed that both bond strength and free end slip are largely affected by both ambient temperature and thickness of the coated film.