A photograph from the Capital One Cup game with Manchester United on 31 October appeared to show the fan making a monkey gesture towards United striker Danny Welbeck.
The man was arrested on Monday after attending a west London police station and Chelsea have acted to prevent him from entering the ground.
"Chelsea Football Club has banned a 28-year-old man from Stamford Bridge pending the conclusion of a police investigation into a possible racially aggravated public order offence," read an official statement.
"The man is not a current Chelsea FC season ticket-holder or member. Chelsea is co-operating fully with the police as they carry out their investigation."
Scotland Yard confirmed he was held on suspicion of a racially aggravated Section 4a Public Order Act offence and he was later released on bail until 29 November.