Japan is one of the world's richest countries but one in six Japanese children now live in poverty - one of the worst rates in the industrialised world.

Poverty is largely hidden in Japan as most go without help for it is seen as a great shame, but the issue is now threatening the country's economic revival.

Nana Kojima is a single mother bringing up two children and is part of Japan's hidden but growing army of working poor.

"I struggle with the rent. Half my income goes on that and then I don't have much left for food and bills," Ms Kojima said.

In Japan more than half a million single mothers live below the poverty line, earning less than $12,000 a year.

Ms Kojima worries that she will not be able to give her children the opportunities needed to lift them out of poverty.

For the moment she has free child care, but that finishes when her son starts school next year.

"There [are] going to be limits on their education. I don't have the money," she said.

"It will be difficult to provide what they need."

Ms Kojima does not receive any child support from her former husband, which is the case for 80 per cent of single mothers.

Community groups call for more government support

Sorry, this video has expired Nana Kojima is part of Japan's hidden but growing army of working poor. ( North Asia correspondent Matthew Carney )

Japan's male corporate culture means single mothers mostly work in casual, low-paid jobs.

Ms Kojima works as a waitress for $10 an hour.

"In Japan, single, working mothers are discriminated against," she said.

"We have little chance to progress as our needs are not understood."

The increase in the number of single mothers is fuelling Japan's record child poverty rates.

Community groups are starting to provide help, including volunteers dedicated to making sure children in need get a healthy meal and their mothers have a chance to connect.

The Children's Network group in Tokyo was one of the first to be set up in the Japanese capital just two years ago and it has encouraged more to be established.

"The mothers can become isolated and have a hard time raising kids," director Chieko Kuribayashi said.

"It's not just about money. We have to create connections to communities so together we can solve the problems."

Ms Kuribayashi says the organisation is just waiting for the government to do its part.

"The government has to set up a proper system to help educate these kids," Ms Kuribayashi said.

"As the children get older, they have to break the poverty cycle and education is the key."