The destructive status of epoxy-coatings on rebar is investigated by the electrochemical spectroscopy.The results show that there is only one time constant while the epoxy-coatings are non-destructive.The time constant reflects the characteristics of epoxy-coatings.The resistance decreases and the capacity increases with the increase of time due to the water in concrete pore penetration into epoxy-coatings.There are two time constants while the epoxy-coatings are destructive.They reflect the characteristics of passive film and electrochemical reaction.The EIS could conveniently and quickly differentiate the destructive status of epoxy-coatings on rebar.It is a useful test method for in-situ and unwounded test the destructive status of epoxy-coatings on rebar in concrete structures.It provides technical support for nondestructive examination of epoxy-coating reinforcement in concrete structures.