The 2010 census indicates 13.26 percent of China's population were at least 60 years old, up 2.93 percentage points from 2000, Ma Jiantang, head of the National Bureau of Statistics, said Thursday.
Ma said the country's birthrate, however, remains low, the state-run news agency Xinhua reported. The current total population is up only 73.9 million from 2000.
The percentage of those 14 or younger fell sharply to 16.6 percent of the total, from 22.89 percent in 2000.
China's 2010 urban population was 665.57 million, or 49.68 percent of the total, up from 36.22 percent in 2000.
Wang Feng, head of the Center for Public Policy at Tsinghua University in Beijing, told The New York Times the numbers show China "has completely turned a page in its demographic history," with very low fertility, quite low mortality and an increasingly urbanized population.
"Such a highly mobile society produces a tremendous dynamism for the Chinese economy and society, and at the same time poses great challenges for the government's political control," he said.
China has followed a policy of one child for many families since 1980.
Professor Yu Xie at the University of Michigan told the Times the increase in the number of college-educated Chinese would "place China in a better position in international competition for economic growth."
Experts note China faces a widening gender gap because of preference for male children. Currently there are 118 newborn boys to 100 newborn girls.
In India, the second-most populated country, the 2011 census measured the population at 1.21 billion, up 181 million from 10 years ago.
China and India together account for 37 percent of the world population.
India is also experiencing a widening gender gap with 914 newborn girls for every 1,000 newborn boys.