Published: 2020-02-04 01:54:12 BdST
The two men have been released under investigation along with a third West Ham fan arrested on suspicion of common assault in a separate incident during the match.
"Police made three arrests at the West Ham United v Brighton football match at the Olympic Stadium on Saturday, Feb 1," a Metropolitan Police spokesperson said in a statement.
"Two male West Ham fans were arrested on suspicion of making homophobic gestures. One male (also a West Ham fan) was arrested on suspicion of common assault.
"They were taken to east London police stations where they were subsequently released under investigation. Enquiries continue."
West Ham said the fans would be banned for life if found guilty of discriminatory behaviour.
"West Ham United is disgusted to hear of alleged homophobic incidents at the game against Brighton & Hove Albion," the club said.
"The matter is now with the police but anyone found guilty of acting in a discriminatory manner will be banned for life from London Stadium and from travelling with the club."