"I'm ready to be the first Iranian to sacrifice myself for our country's scientists," Ahmadinejad told scientists in Tehran during a ceremony where two new Iranian-made satellites were unveiled.
The ceremony was part of Iran's national day of space technology, the semiofficial Mehr News Agency said.
Ahmadinejad said he would join the monkey, mouse, turtle and worms Iran had sent into space, predicting Iran's fledgling space program would send humans into space within five years.
"Sending living things into space is the result of Iranian efforts and the dedication of thousands of Iranian scientists," he said.
It was unclear if Ahmadinejad's suggestion was serious, but a Facebook page created within minutes of the news breaking was filled with people declaring they would do everything they could to help Ahmadinejad achieve his goal.
One user on the "In support of sending Ahmadinejad into space" page wrote, "We will accompany him to the platform, we will even pay for the shuttle's fuel costs."
The page, which shows Ahmadinejad's smiling face inside an astronaut's helmet, had about 1,000 "likes" when United Press International checked early Tuesday.
In the United States, Sen. John McCain, R-Ariz., created a bit of a flurry when he sent a Twitter message Monday suggesting Ahmadinejad was the monkey Iran sent into space -- a joke that at least one fellow Republican saw as having racist overtones.
"So Ahmadinejad wants to be first Iranian in space -- wasn't he just there last week?" McCain's message said.
Rep. Justin Amash, R-Mich., sent a Twitter message shortly afterward, saying, "Whoa."
McCain responded: "Re: Iran space tweet - lighten up folks, can't everyone take a joke?" To which Amash replied, "Maybe you should wisen up & not make racist jokes."
Ahmadinejad's second and final term as president ends in June. His political influence has been waning since he had a falling out with Parliament early in his second term and is widely believed to have lost the support of Iran's supreme leader, Ayatollah Ali Khamenei.