Singles Day, also known as Double Eleven because it is held on 11 November, has become a major annual event for Chinese retailers.
Alibaba said more than $1bn was spent within eight minutes of midnight.
Within an hour, it had made $3.9bn (£2.bn) in sales, almost double the amount spent in the same time period of the event last year.
In comparison, sales on Cyber Monday, which is the biggest online shopping day in the US, hit $1.35bn, according to analysts ComScore.
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