He was caught by passers-by when he was taking pictures under a woman's skirt on an elevator using his cellphone.
He was detained by the police from Metro Line 1's People's Square Station in Shanghai, China's most populous city and a business hub, yesterday.
The man has been taken for questioning by the police.
He will receive administrative detention according to the law, Shanghai Daily quoted police as saying.
A video of the man being roughed up at the metro station has gone viral on Chinese social media.