A recent report from a top government think-tank shows pressure is growing on China's urban poor, who face rising living costs, low wages, and a polluted environment.
The report, published last week by the prestigious China Academy for Social Sciences (CASS), said the total number of urban poor reached 50 million in 2009, a level some experts think has been seriously underestimated.
The Chinese urban middle class, by contrast, numbered around 230 million in 2009, and was projected to grow to around half the urban population by 2023, based on current economic performance.
Middle-income urban residents now make up 37 percent of the total urban population, according to the "China Urban Development Report 2011."
The report defined middle-income families as those who spent between 30 percent and 37.3 percent of their income on food.
However, some experts have pointed out that higher-income Chinese people eat out frequently, while poorer people almost never do, rendering the measurement of relative poverty faulty.
Jason Z. Yin, a professor of strategy management and international business at Seton Hall University, said that China is in the process of intensive urbanization, with huge numbers of rural residents flooding into cities in search of work.
"This has led to a lot of problems," Yin said. "But it is also an inevitable result of economic development."
He said the millions of rural people seeking work in China's cities receive low incomes and live in substandard accommodations, as well as lack any kind of income security.
Meanwhile, Wu Kegang, China adviser to the British Chamber of Commerce, said it is important to take the figures on urban poverty in a wider context.
"Overall, we shouldn't say that the standard of living has got lower and lower as a result of urbanization," Wu said. "We can be sure that the overall direction ... has been one of a steadily increasing income for ordinary Chinese people."
He said the problems faced by China's urban poor are a side effect of widespread structural changes to the national economy.
"The main problem for national policy now is whether China's wealth should be redistributed through the tax system or through the mechanism of wages," Wu said.
"You can have a minimum wage or subsistence welfare payments, but all of these involve the issue of the redistribution of wealth."
Yin said things are unlikely to get any easier for China's urban poor until there is enough residential property available to bring down prices.
"I don't think anyone in the various levels of China's government has the motivation to do this," he said.
But he added: "Secondly, there isn't a country in the world that can guarantee homes to all of its citizens ... In a huge country like China, [that] would be impossible."
In June, riots by migrant workers in a Guangdong factory town highlighted gaping social inequalities between Chinese people with rural and urban registration papers.
Threat to stability
The same month, a government think-tank warned that China's millions of rural workers will become a serious threat to stability unless they are better treated in their new urban locations.
Migrant workers moving to towns and cities to seek work in factories are often treated as unwelcome interlopers, and enjoy much less access to public services like education, welfare payments, and health care than those who are registered as already living in the town.
A report from the State Council Development Research Center in Reform magazine said rural migrant workers are not only marginalized in cities and treated as mere cheap labor, but even neglected, discriminated against, and harmed.
A number of Chinese cities have recently begun raising the minimum wage in an attempt to close the growing gap between rich and poor.
Labor experts say today's migrant workers in China's big cities are less likely to accept unfair treatment or inadequate pay and conditions in urban factories, because the new generation is highly motivated and better educated than their parents.
Social scientists say few of those who make the move to cities will be willing to return to their rural homes.
Reported by Yang Jiadai for RFA's Mandarin service. Translated and written in English by Luisetta Mudie.