Williams, the three-time former champion, beat the Russian 6-3 6-4.
This match put together two of the most aggressive players on the circuit and almost immediately it was evident that both were going for big serves and lots of winners.
The first set was one of the best of the Championships so far. Both players hit ten winners each, often after some long and gruelling rallies.
Analysis: Bronze medal Tim
Williams broke the Russian's serve in the seventh game and powered through the rest of the set.
In the second set the 2000 and 2001 champion was just as strong and the fifth seed had to save three break points in the first game before being broken in game five.
But Kuznetsova then took advantage of some swirling winds on Venus' serve to break back only for Williams to do likewise in game seven.
In the last two games as Williams closed in, the strain of facing such a powerful serve showed in Kuznetsova's play, and Williams' relentless pressure in rallies drew errors that saw the 23rd seed seal victory in 85 minutes.
The 2005 champion will face Ana Ivanovic in the semi-final, after the Serb beat Nicole Vaidisova 4-6 6-2 7-5.
The finalist at Roland Garros, seeded sixth here, got off to the worst possible start, having her serve broken in the very first game.
After that, 14th seed Vaidisova never looked uncomfortable on her own serve but apart from two wasted break points in the fifth game never looked like breaking the Serb's serve again. After a rain break that lasted all of two minutes, the rest of the set went with serve, Vaidisova taking it 6-4.
Any hopes of Ivanovic had of coming out of firing out of the blocks for the second set were dashed as she again dropped her serve in the first game.
She dug deeper this time, and on her third break point of the following game lifted a delicate drop shot over the net, just out of Vaidisova's reach.
The Serb broke again on her way to taking the match the full distance, winning the second set 6-2.
At the third time of asking Ivanovic held her serve at the start of a set. However, Vaidisova broke her at the next opportunity to go 2-1 ahead.
With her back against the wall Ivanovic broke back in the tenth game, having previously saved three match points.
From then on Vaidisova's game deserted her, and she served a double fault on match point to give the 20-year-old Serbian her path to the semi-finals.
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