The snap shows the pop singer sitting on a leather couch apparently wearing nothing but a coloured head scarf, with his hand covering his crotch.
It was posted online by Styles' cousin Matt Selley, who is seen in the picture along with his brother Ben Selley.
Matt captioned the snap, "Just watch the fight from last night (sic)! Class!" in reference to a televised boxing match between Carl Froch and George Groves in London on Saturday (31May14).
The snap has since been shared more than 16,000 times via Twitter.com.
Styles' nude snap controversy comes just days after his bandmates Louis Tomlinson and Zayn Malik were caught up in a drug scandal after video footage which appeared to show them smoking marijuana while on tour in Peru surfaced online.