British Transport Police made the arrest on 5 July.
A spokesperson for BTP said:
‘At 23:12 on Tuesday 5 July, officers were made aware of a report of a sexual assault at Nottingham station.
‘Officers arrived on the scene two minutes later and speak with the victim.
‘A description of the offender is circulated.
At 23:17 further officers locate and arrest the suspect on suspicion of sexual assault by touching.’