WIKILEAKS editor-in-chief Julian Assange might be unpopular with the US and its allies, but he's still mummy's little boy.

Mr Assange's mother, Christine, who doesn't even own a computer and has been keeping up with her son's exploits through the media, said her son was a "seeker of truth".

Ms Assange, who bought Julian his first computer at age 13, said her son had been a curious child, raised to believe evil flourished when good men did nothing.

"Whether you agree with what Julian does or not, living by what you believe in and standing up for something is a good thing," she said.

"He sees what he's doing as doing a good thing in the world, fighting baddies, if you like."

But she conceded she feared her 39-year-old son had "gotten too smart for himself".

"Of course, I'm his mother, he's my little boy," she said.

"I'm just a normal mother. Whatever a normal mother would feel is what I would feel about all of it.

"I'm concerned it's gotten too big and the forces that he's challenging are too big."

Ms Assange said her "highly intelligent" son was brought up without religion, but with a strong code of ethics.

"He was lovely boy, very sensitive, good with animals, quiet and has a wicked sense of humour," she said.

"What people don't realise is that Julian is very funny.

"He didn't actually come from a background of high technology; he came from a background of creativity and a love of learning and books."

At 18, Mr Assange became a father when his son, Daniel, now 21, was born.

"Jules put his life and university studies on hold to parent Daniel and be there for him," Ms Assange said.

"He's a very good father - not many men of that age will fight for their kid, but he stepped up to the responsibility.

"To me that's an even greater achievement than WikiLeaks."

Father and son even attended university together when Daniel began his masters degree in genetics, aged 15, and his dad studied mathematics and physics at the University of Melbourne.

Ms Assange, who moved to the Sunshine Coast five weeks ago for health reasons, said Julian was distancing himself from the family for their own safety.

Originally published as WikiLeaks founder's mum defends son