It was Williams' second straight Wimbledon women's singles title, surging through the last set to defeat Henin 6-1, 3-6, 6-0.
The final, which should have been staged on Saturday, had been delayed a day because of rain.
The men's finals will be held Monday: Pat Rafter versus Goran Ivanisevic.
|Another trophy for her case.|
But Williams' power took control in the third set as she broke three times, winning the title when Henin, under pressure on the baseline, was unable to control her shot and fired it tamely wide.
Unlike last year, when she celebrated with a victory leap, Williams was more reserved this time.
"I couldn't leap because it was raining," she said. "I didn't want to fall."
Williams started the final with two double faults and didn't get her first serve in until the fifth point when she served an ace. But she won four points in a row to hold serve.
Henin, who defeated Williams 6-1, 6-4 in their only previous meeting on clay in Berlin in May, had two aces in a confident first service game.
|Henin lost the first set in just 20 minutes.|
The defending champion squandered the first when she fired a backhand wide but, when Henin sent up a lob under pressure, Williams clinched the set in 20 minutes with an easy smash.
After a 15-minute rain delay, both players held before Williams fired a backhand wide to hand two break points to the Belgian and, when the defending titleist netted another, Henin led 5-3.
When Williams put another backhand out, Henin had two set points and luring the American to the net, punched a backhand past her to take the set.
Williams said she was "a little bit angry" after losing the second set, but was more relaxed afterward.
"I thought I could have played better," she said.
After holding in the opening game of the deciding set, Williams broke in the second. Although Henin saved two break points to twice bring the game back to deuce, she surrendered a third by netting a low backhand.
Williams then held for a 3-0 lead and had two more break points when Henin netted a forehand. The Belgian saved the first when Williams' return was long but the American broke again when Henin fired a forehand long.
With rain falling again, Williams appeared in a hurry and a fourth double fault handed Henin an opening at 15-30. But the American won three points in a row to move ahead 5-0.
Henin's third double fault followed by two netted forehands gave Williams two championship points. Although Henin saved the first with a service winner, the defending champion clinched the title with some powerful strokes that the Belgian teen-ager was unable to handle.
"She was a great champion," said Henin, who defeated Jennifer Capriati in the semifinals. "She played better than me today."
"In the third set, mentally, she was stronger."
Williams, who will defend her U.S. Open title later this summer, was a strong favorite to hold on to the championship she won last year by beating countrywoman Lindsay Davenport.
Williams had dropped just one other set on the way to Saturday's match, a tiebreak against Davenport.
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