A video posted on YouTube which captures a mother racially abusing a school boy on a Sydney bus is the latest in a string of similar attacks on public transport in Australia.

The 4-minute clip - which aired on Current Affair in Australia last night - shows the boy, who is of Asian descent and in a school uniform, and his friend trying to protect fragile equipment while travelling on a city bus.

Upset that the boys are blocking her view, a 50-year-old woman sitting behind the pair launches her attack.

Telling the boy to "Sit the f*** down," the woman adds "I'm born here, I know what I'm doing. Go back on your f***ing boat and f*** off."

The passenger who filmed the ordeal told news.com.au the tirade lasted about 12 minutes and was witnessed by dozens of Asian school children also travelling on the bus.

While he wished to remain anonymous, the passenger said he posted the clip to YouTube in order to shame the woman and highlight the rampant problem of racism on Australian public transport.

"It's going on and it [racism] doesn't look like it's stopping, I think they should put more effort into getting rid of this kind of behaviour in the public transport system," he told news.com.au.

This isn't the first time racism on the Australian public transport network has been caught on camera.

In November last year, French woman Fanny Desaintjores said she feared for her safety when she was threatened with racial taunts by two men and a woman who took issue with her singing in French on a Melbourne bus.

Early this year, ABC News presenter Jeremuy Fernanadez endured 15 minutes of racial abuse on a Sydney bus before being kicked off by the driver, who blamed him for the incident.

Another incident in April saw a woman, originally from the Philippines, endure a racist rant on a busy Melbourne bus.

"Being humiliated in front of a packed [train] full of passengers - it's like your dignity has been removed from you, I'm traumatised by it," she told 3AW radio.

- www.nzherald.co.nz