Jeremy Corbyn's son was mugged in his father's constituency after a man on a moped snatched his mobile phone.
Tommy Corbyn, 23, said the thief tried to "run me over" in the theft on Sunday evening.
He had been walking through Holloway in north London at the time.
Mr Corbyn, who is the youngest son of the Labour leader, shared details of his experience online, urging friends who "walk and text" to be vigilant, the Evening Standard reported.
He added: "The real sad part is that someone was willing to try and run me over with a moped for a phone he’ll struggle to get 50 quid for!
“Just want others to learn, we all walk around like Zombies and wonder why people take advantage.
“I’m sure the guy who did it was more desperate than bad and I’m glad it happened to me not someone who would have been badly affected by it."
He described the theft as "pathetic" and said he hoped others would not make the same mistake.
Scotland Yard has not commented on the incident involving Mr Corbyn.
Last year he reported to police that he was headbutted outside a nightclub in York, where he was studying electrical engineering.
An average 22 robberies by people on mopeds take place in the capital each day, with frequent incidents where riders mount the pavement and grab phones from distracted pedestrians.
Just last week two thieves who snatched 18 mobiles in one day from people as they made calls were jailed. Zuriel Hutson, 21, and Sharuk Sheraji, 22, rode a stolen high-powered moped and carried out a series of thefts across London on November 26 2016.
With Hutson steering and Sheraji as pillion, the duo carried out the crimes across the city. Hutson was sentenced two and a half years' imprisonment and Sheraji was jailed for two years.