Button started on the pole and quickly broke away from the field on the opening lap. He gave up the lead briefly when he pitted twice during the 78- lap event. Button crossed the finish line 7.666 seconds ahead of his teammate, Rubens Barrichello, to give Brawn GP their third one-two finish this year.

"I got off the (green) light clean and had Rubens behind," Button said. "Rubens had problems with his rear tires, and I was able to pull a gap. It really didn't change much from there, except for traffic."

Button, who resides in the Principality, became the first Briton to win the Monaco GP from the pole since Jackie Stewart did it in 1973.

After taking the checkered flag, Button parked in the wrong place and had to jog part of the 2.075-mile street circuit with his helmet still on to reach the podium ceremony site, where he was handed the winning trophy by Prince Albert II.

"The race was pretty tough, but that deal with the helmet on, you realize how long that pit strategy was," he said. "But in a way it was a difficult way to end the race."

Barrichello started third but overtook Kimi Raikkonen for second heading into the first corner on the opening lap.

"Just like Barcelona, I had a great start," Barrichello said. "I was able to have a run on Kimi, and then I was running a tremendous pace. It was really good behind Jenson."

Barrichello finished second in the Monaco GP for the fourth time. He was also the runner-up here in 1997, 2000 and '01.

Ferrari improved much after a disastrous start to the season, with Raikkonen finishing third and Felipe Massa coming in fourth.

"It's not the first time I've been in second place and fell one position at the start," Raikkonen said. "We lost a lot of time in the beginning, and that was the only time to stay behind Jenson."

Mark Webber from Red Bull Racing completed the top-five.

Nico Rosberg from Williams finished sixth, followed by Renault's Fernando Alonso, Toro Rosso's Sebastien Bourdais, Giancarlo Fisichella from Force India and Toyota's Timo Glock.

McLaren's Lewis Hamilton, the defending world champion and last year's winner at Monaco, started 16th and finished one lap behind in 12th.

Button extended his world championship points lead to 16 over Barrichello.

"I think we've proven this weekend that our package works, and I think we're looking strong for the next few races," Button said.

The Monaco GP ran relatively incident free with little overtaking.

Sebastien Buemi plowed into the back of Nelson Piquet as the two ran off course on lap 11. Both drivers were the first to retire after suffering front end damage to their cars.

Sebastian Vettel, the only other grand prix winner so far this year, hit the barriers on lap 17 as his race came to an early end. Vettel finished 18th. He won the Chinese Grand Prix last month.

BMW Sauber's season woes continued, as Robert Kubica wound up 17th after he suffered engine failure midway through the event. Kubica finished second to Hamilton at Monaco one year ago.

Kubica's teammate, Nick Heidfeld, came in 11th.

Heikki Kovalainen from McLaren spun finished 16th after slamming into the "swimming pole" barrier on lap 52.