The most active crude oil contract for June delivery was down 6.6 yuan (about 94 U.S. cents) to close at 285.1 yuan a barrel.
The total trading volume for 18 listed crude oil futures contracts on the exchange was 199,777 lots, with a turnover of about 59.91 billion yuan.
China launched the crude oil futures trading, which is open to overseas investment, in March 2018.
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