The military organisation, loyal to Iran’s supreme leader – said the order was “irrevocable” on the eve of the anniversary of the 1989 fatwa.
The order was issued after publication of Mr Rushdie’s novel “The Satanic Verses”, condemned as blasphemous.
Iran’s reformist government has in the past distanced itself from the fatwa.
The Revolutionary Guards, who answer directly to Iran’s current Supreme Leader Ayatollah Ali Khamenei, said: “This statement, while stressing the irrevocability of the death verdict against Salman Rushdie, says history shows that the Muslims have in no era accepted their sanctities being defiled.”
“The day will come when they will punish the apostate Rushdie for his scandalous acts and insults against the Koran and the Prophet (Mohammed),” they said, two days before the anniversary of the order.
Torn relations
The fatwa, which was issued by the late Ayatollah Ruhollah Khomeini, disrupted Iran’s relations with the EU though the 1990’s.
The guards’ statement comes a month after Ayatollah Khomeini’s successor Ayatollah Khamenei said he still believed the British novelist deserved to die.
“They talk of respect for all religions but they support an apostate worthy of death like Rushdie,” he said.
The BBC’s Frances Harrison reports from Tehran that religious authorities in Iran say the only person who can lift the sentence was the man who imposed it, Ayatollah Khomeini, who died in 1989.
Iran’s reformist President Mohammad Khatami has previously said the death sentenced should be considered closed.
In 1998, Tehran promised the British Government that Iran would do nothing to implement the fatwa.
The pledge eased nearly a decade of torn relations with the EU but sparked a chorus of protest from hardliners.
Last year, the Khordad Foundation, a charity that put a $2.8 million bounty on Mr Rushdie, declared the fatwa remained valid.
Since the 1989 decree, Mr Rushdie has received constant protection in the UK.
He has had to keep his whereabouts secret and lived in 30 different addresses in the UK over nine years.
