Serena Williams defeated the two-time defending champion, her sister Venus Williams, in a rematch of the previous year's final, 7–6(7–3), 6–2 to win the ladies' singles tennis title at the 2009 Wimbledon Championships. It was her third Wimbledon singles title and eleventh major singles title overall. It was also the third time she won a major after saving a match point, which occurred in the semifinals against Elena Dementieva. Serena dropped only one set the entire tournament, to Dementieva in the semifinals.
Venus Williams was attempting to become the first player to win the tournament three consecutive times since Steffi Graf in 1991, 1992 and 1993.
This edition of the tournament saw the top four seeds all reach the semifinals, the most recent occurrence of this happened at a major (as of 2023). The match between Serena Williams and Dementieva was the longest women's semifinal at Wimbledon in the Open Era, lasting two hours and 49 minutes, before the record was broken at the 2024. 
Seeds.
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1.   Dinara Safina "(semifinals)"
2.   Serena Williams (champion)
3.   Venus Williams "(final)"
4.   Elena Dementieva "(semifinals)"
5.   Svetlana Kuznetsova "(third round)"
6.   Jelena Janković "(third round)"
7.   Vera Zvonareva "(third round, withdrew due to an ankle injury)"
8.   Victoria Azarenka "(quarterfinals)"
9.   Caroline Wozniacki "(fourth round)"
10.   Nadia Petrova "(fourth round)"
11.   Agnieszka Radwańska "(quarterfinals)"
12.   Marion Bartoli "(third round)"
13.   Ana Ivanovic "(fourth round, retired due to a thigh injury)"
14.   Dominika Cibulková "(third round)"
15.   Flavia Pennetta "(third round)"
16.   Zheng Jie "(second round)"
17.   Amélie Mauresmo "(fourth round)"
18.   Samantha Stosur "(third round)"
19.   Li Na "(third round)"
20.   Anabel Medina Garrigues "(third round)"
21.   Patty Schnyder "(first round)"
22.   Alizé Cornet "(first round)"
23.   Aleksandra Wozniak "(first round)"
24.   Maria Sharapova "(second round)"
25.   Kaia Kanepi "(first round)"
26.   Virginie Razzano "(fourth round)"
27.   Alisa Kleybanova "(second round)"
28.   Sorana Cîrstea "(third round)"
29.   Sybille Bammer "(first round)"
30.   Ágnes Szávay "(first round)"
31.   Anastasia Pavlyuchenkova "(second round)"
32.   Anna Chakvetadze "(first round)"
"Click on the seed number of a player to go to their draw section."
Draw.
Key.
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References.
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