The 28-year-old, on loan at Everton, has been interviewed by police in connection with an incident which took place on Sunday April 5 at Suede night club in the city centre.
Lennon, who is in Everton’s squad to face Manchester United on Sunday, is believed to have voluntarily attended a police station a fortnight ago
A police spokesperson told Sky Sports News HQ: “On Wednesday April 8, 2015, police were called following reports an 18-year old woman had been assaulted at Suede night club, Longworth Street, Manchester city centre on Sunday 5 April 2015.
“A man has been interviewed under caution. No arrests have been made and enquiries are ongoing.”
Lennon joined Everton on a deal until the end of the season in January, having struggled to hold down a first-team place under Mauricio Pochettino.
He has made 10 appearances for the Toffees, scoring two goals, and will hold talks with the club over a possible permanent move to Goodison Park in the summer.