The One Direction singer, who turned 19 this week, was pictured with bandmate Niall Horan and Radio 1 DJ Nick Grimshaw at Rita's Bar and Grill in Dalston, London.
Pictures in The Sun showed Styles chatting to his friends as the girl danced and removed her clothing.
Grimshaw and Styles posed for a picture with the unnamed dancer, who dressed as a policewoman for the performance.
Horan later reportedly told a fan on Twitter that his bandmate was "so shocked" and he had "never seen [Styles] so scared before".
Earlier in the week, Styles was pictured celebrating his birthday with Grimshaw, comedian James Corden and former girlfriend Caroline Flack.
Photo gallery - Harry Styles's bithday celebrations:
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