The sexual assault is alleged to have taken place in the Newgate Lane area of the town on New Year’s Day.
The CCTV footage of the man was captured by cameras in Illusions nightclub, Clumber Street, Mansfield.
He was in the nightclub prior to the assault taking place.
Police are asking anybody who might have been in the nightclub or who might recognise this man to come forward.
If you have any information contact Nottinghamshire Police on 101 quoting incident number 532 of 1 January 2016 or Crimestoppers anonymously on 0800 555 111.
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