Abstract: This invention provides a novel dry chemical process for removing by carbonylation the metals harmful to the catalyst activity from the catalyst for the residuum and/or heavy oil catalytic cracking, comprising: contacting the catalyst contaminated by the poisonous metals with an activation gas and a reduction gas in a reactor for activation and reduction; and then in a carbonylation reactor, contacting the catalyst treated by activating and reducing with CO gas to make the metals on the catalyst carbonylated to form gaseous metal carbonyls which are then transferred and separated from the solid catalyst, thereby the catalyst activity is restored. The process of this invention is simple in the technology, moderate in the operation conditions, and it will not cause secondary pollution to environment for there is no addition and discharge of any liquid.