Mofaz said: "The policies followed by ElBaradei endanger world peace.
"His irresponsible attitude of sticking his head in the sand over Iran's nuclear programme should lead to his impeachment."
ElBaradei angered Israeli officials by telling France's Le Monde newspaper earlier this week that Iran would need "between three and eight years" to develop a nuclear bomb and that there was no immediate threat.
The Egyptian UN nuclear chief said: "I want to get people away from the idea that Iran represents a clear and present danger and that we're now facing the decision whether to bombard Iran or let them have the bomb.
"We're not in that situation at all."
Mofaz said there was no excuse for that view in the face of intelligence estimates.
"ElBaradei says he has no proof regarding Iran's nuclear programme when he has intelligence reports gathered by several countries and he heads an organisation responsible precisely for that," he said.
The comments coincided with an Israeli newspaper report that quoted Ehud Olmert, the prime minister, as telling confidants in private conversations that ElBaradei, an Egyptian, was "no fan" of Israel.
Mofaz, who heads "the strategic dialogue" between Israel and its main ally, the United States, held talks on Wednesday in Washington with Condoleezza Rice, the US secretary of state.
Tehran rejects accusations it is seeking to develop a nuclear bomb, saying it wants nuclear technology for peaceful purposes such as power generation.
Iran has refused to heed UN Security Council demands to halt enrichment.