New York's main contract, light sweet crude for delivery in December, retreated 23 cents to $97.55 per barrel. Brent North Sea crude for December delivery shed 61 cents to $113.10.
Crude traders were making a quick buck after prices shot up in late US trade Thursday, said Victor Shum, senior principal of Purvin and Gertz energy consultants in Singapore.
"It's simply profit-taking after the big comeback yesterday in the US," he told AFP.
"It was a confluence of a lot of positive economic news in the US and Europe, and some data from China on growth in its oil imports last month," Shum added.
The US had a rare reprieve from its economic woes on Thursday as government data showed the trade gap of the world's largest oil consumer narrowed in September and unemployment claims fell to a seven-month low last week.
European debt worries were also slightly eased as Greece named a new prime minister and Italy's borrowing rate fell from unsustainable levels reached on Wednesday.
Figures issued Thursday showing stronger than expected oil imports by China, the world's biggest energy consumer, also boosted oil markets overnight.