Bush was going quite fast on the presidential bicycle when he collided with an officer guarding the Gleneagles golf resort, said White House spokesman Scott McClellan.
Bush slid along the road, suffering scrapes on his hands and
arms that were bandaged by Dr Richard Tubb, the president's
"He was wearing a helmet," spokesman McClellan said. "The accident occurred on asphalt. His scrapes were mild to moderate."
It is the second reported bicycle accident during his presidency - last year he fell off his mountain bike at his ranch in Texas, suffering slightly more serious injuries.
A spokeswoman for the UK's Tayside police, tasked with guarding the leaders of the G8 nations said the policeman also sustained a very minor ankle injury.
Bush later appeared unhurt at
Queen Elizabeth's banquet
The president, who had been riding with a Secret Service agent, was fine, McClellan said. But the bicycle suffered some damage and Bush had to return to the hotel in a car, which had been trailing them.
The US leader later appeared unhurt when he joined a banquet hosted by Queen Elizabeth II at the Gleneagles hotel for the leaders of Britain, Canada, France, Germany, Italy, Japan, Russia and the United States.
During his presidency, Bush has also managed to fall off a Segway - a motorised, two-wheel vehicle - in Kennebunkport, Maine, in June 2003.
He has also suffered scrapes to his face when he fainted and fell after choking on a pretzel at the White House in January 2002.