This is the fourth time that Williams has been the top seed at the US Open, reports Xinhua.
Simona Halep of Romania -- runner-up at the French Open last year -- has been seeded second. The 2006 US Open champion Maria Sharapova of Russia is the third seed while 2014 US Open finalist Caroline Wozniacki of Denmark is the fourth seed.
Petra Kvitova of the Czech Republic, the Wimbledon champion in 2011 and 2014, is the fifth seed while compatriot Lucie Safarova, who reached the final of this year's French Open, is the sixth seed.
The 2015 US Open will be played from August 31 to September 13 at the USTA Billie Jean King National Tennis Center in Flushing Meadows, New York.