Police arrested seven men after violence broke out when West Ham played Chelsea at the former Olympic Stadium.
Scotland Yard said the men were arrested for public order offences following the clash at the London Stadium, in Stratford, east London.
A further 30 people were issued with directions to disperse under antisocial behaviour legislation ahead of the EFL Cup match on Wednesday, the Metropolitan Police said.
The force said it deployed a "significant number" of officers in the stadium to deal with the "unacceptable" scenes at the derby match.
Commander BJ Harrington, who led the operation, said: "Although the vast majority of people left the stadium peacefully and were well behaved, there were a minority of people who attended the match that were clearly intent on being involved in confrontation and violence.
"Despite extensive work with both clubs and the London Stadium partners as well as a large and robust policing operation, there were unacceptable incidents inside and outside the stadium, before, during and after the game.
"We have already made seven arrests and will work tirelessly to identify people involved and bring them to justice."
Both clubs issued statements condemning the skirmishes, the circumstances of which are under investigation by police.
Missiles including coins and seats were launched between rival fans.
And stewards struggled to maintain segregation behind the Hammers' goal towards the end of the match, which West Ham won 2-1.
West Ham manager Slaven Bilic described the scenes as "unacceptable", while the club "unreservedly" condemned those involved, who they will seek to identify.
The club said: "Once identified, those found to have acted improperly will be banned from attending any West Ham United fixtures for life and we will request the courts serve banning orders to prevent these individuals attending any other football."
The London Stadium has been West Ham's home for nine games after leaving the Boleyn Ground in Upton Park in May.
A Chelsea spokesman said: "The club is extremely disappointed to see disturbances at the end of tonight's game and we condemn such behaviour."