"Muslim immigration into the United States should be stopped until we can properly vet them or until the war with Islam is over," he said.
Mr Trump, who is standing to be the Republican candidate for the US Presidential Elections, provoked widespread anger and ridicule after demanding a block on Muslims entering the US and claiming parts of London were "so radicalised" that police were "afraid for their own lives".
He made the call for a "total and complete shutdown" of Muslims entering the US in the wake of last week's terror attack in San Bernardino, California, where a Muslim couple believed to have been radicalised shot 14 dead at a health centre.
On his Facebook page Franklin Graham said he had agreed with the proposal "for some time".
He quoted an unverified poll which he claimed said 29% of Muslim under 45 believed violence against America is justified in order to make Sharia the law of the land.
Mr Graham said that was "frightening".
He added: "Our politicians are not listening to the truth-my prayer is that God will open their eyes.
"This affects our security and the future of our nation."
Meanwhile more than 390,000 people have backed a call for Donald Trump to be banned from the UK after his comments.
Thousands rushed to sign a petition on the Parliament website as British politicians lined up to condemn the remarks.
