Jodie Henry became the first Australian since the great Dawn Fraser to win the Olympic 100 metres freestyle title when she surged past her rivals to scoop gold in an exciting final on Thursday.

The 20-year-old was slowest of the eight finalists out of the blocks and trailed fifth at the turn when defending champion Inge de Bruijn and American Natalie Coughlin led the way.

But there was little dividing them and Henry charged past on the return length, with De Bruijn in brave pursuit, to become the first Australian winner of the event since Fraser achieved the last of her three consecutive titles in 1964.

Henry hit the wall in 53.84 seconds, outside the 53.52 world record she set in Wednesday's semi-finals but that was of no consequence because the gold was hers and Australia could celebrate their fifth swimming title of the Games.

It was Henry's second gold after anchoring the Australian 4x100 freestyle relay to victory last Saturday.

"My main event was the 4x100 (freestyle relay) so this is just a bonus," said Henry.

Asked if De Bruijn had said anything to her before the race, Henry said: "I think she was trying to psyche me out.

"She was facing me and I though 'this is sad'," she added. "I did start laughing and I just started waving at everybody. I wasn't going to let her bum me out."

De Bruijn took the silver in 54.16 and Coughlin the bronze in 54.40 to augment her Athens medal collection, which already includes three golds.

European champion Malia Metella of France was fourth, 0.10 seconds behind.

De Bruijn, triple champion at the 2000 Sydney Olympics, has now lost the second of her three titles, having had to settle for bronze in Sunday's 100m butterfly defence.

The Dutch sprinter, who celebrates her 31st birthday next Tuesday, contests the 50 metres freestyle heats on Friday.

The 20-year-old was slowest of the eight finalists out of the blocks and trailed fifth at the turn when defending champion Inge de Bruijn and American Natalie Coughlin led the way.

But there was little dividing them and Henry charged past on the return length, with De Bruijn in brave pursuit, to become the first Australian winner of the event since Fraser achieved the last of her three consecutive titles in 1964.

Henry hit the wall in 53.84 seconds, outside the 53.52 world record she set in Wednesday's semi-finals but that was of no consequence because the gold was hers and Australia could celebrate their fifth swimming title of the Games.

It was Henry's second gold after anchoring the Australian 4x100 freestyle relay to victory last Saturday.

"My main event was the 4x100 (freestyle relay) so this is just a bonus," said Henry.

Asked if De Bruijn had said anything to her before the race, Henry said: "I think she was trying to psyche me out.

"She was facing me and I though 'this is sad'," she added. "I did start laughing and I just started waving at everybody. I wasn't going to let her bum me out."

De Bruijn took the silver in 54.16 and Coughlin the bronze in 54.40 to augment her Athens medal collection which already includes three golds.

European champion Malia Metella of France was fourth, 0.10 seconds behind.

De Bruijn, triple champion at the 2000 Sydney Olympics, has now lost the second of her three titles, having had to settle for bronze in Sunday's 100 butterfly defence.

The Dutch sprinter, who celebrates her 31st birthday next Tuesday, contests the 50 metres freestyle heats on Friday.

Henry, last year's world championship silver medallist, had beaten De Bruijn by half a second in the semi-finals to establish herself as a strong favourite for gold.