Abstract: Through macro morphology observation, chemical composition analysis, scanning electron microscopy and energy dispersive spectroscopy, the reasons for corrosion of the colored plate of Q235 as an enterprise′s workshop were analyzed, and the improved measures were also put forward. The results indicated that serious corrosion of the colored plate was due to a joint action of high temperature air, oxygen corrosion, and sulfur corrosion. The high concentration of sulfur dioxide in the of workshop roof was the main reason for the increased corrosion rate. It is suggested to spray antirust paint or polyurea material on the color steel surface, improve production process and do regular check and online inspection.