Earlier this month, he surrendered the Conservative whip while he considers an appeal of his conviction for a racially aggravated public order offence.
The Beckenham MP was found guilty at Westminster Magistrates’ Court of racially abusing an activist by telling him to “go back to Bahrain”.
In a statement on X, Mr Stewart said: "Serving Beckenham as its Member of Parliament for 13 years has been an honour and privilege.
"I am incredibly grateful to everyone who has given me this opportunity.
"However, it is time for a new candidate, so I will not be seeking re-election at the next election."
During a heated exchange, Stewart replied: "Go away, I hate you. You make a lot of fuss. Go back to Bahrain."
Rishi Sunak faced immediate calls to suspend Mr Stewart as a Tory MP following the conviction, for which he was handed a £600 fine.