The white passenger hurled verbal abuse at the unidentified woman who was travelling with her children when she politely asked him to watch his language.
The dark-haired man, who appears to be in his 20s, who also claimed he was carrying a knife during the incident last week.
In a video taken by another commuter, the man can be heard shouting: “Some silly **** black bird trying to **** tell me to shut up.
The woman replied and said: “There’s no need to be so aggressive. I’m not shouting at you. I wasn’t shouting at you.”
He then shouts to the same woman who was sitting down: “Why have you got up shouting at me?
“Shut your **** mouth. Shut up. Shut up. You’re moaning about the way that I’m talking, you shut up. Shut up silly ****.”
The man threatened two other men on board the train intimidating that he was in possession of a knife.
However, a knife was not seen during the incident.
The indecent happened at around 2:45pm on April 6 between Fenchurch Street station and Shoeburyness station
British Transport Police are appealing for help in tracing the man who got off the train at Leigh-On-Sea, Essex.