Beijing's population is likely to soar to 20 million by 2020, largely because of the continued influx of migrants from other parts of the country, experts predicted.
A report released by the Population Institute of Peking University provides a likely map of the capital's population demographic in the coming decade.
Beijing's current population is about 15 million.
Of the predicted population in 20 years, 12 percent will be considered aged, and up 13 percent will be younger people, the report said, highlighting there could be challenges for the labor and social services sector to support such a population.
The report, the result of three years research, should help the municipal government plan for policy adjustments in areas including social welfare, education, housing, and medical services.
"Actually, the unveiling of the report is just a stopover before we embark on a series of new and related research based on this report," Pang Lihua, a demographer and one of the contributors to the report, told China Daily.
Statistics show the city's birth rate has been slightly lower than the death rate in previous years, with a narrowly higher birth rate this year and last year caused by couples wanting to have a child during this auspicious birth year.
But Yang Hui, a researcher with Beijing-based Renmin University of China, warned that an aging society puts "great pressure" on a city's medical rescources and a "burden" on the workforce.
For the past 50 year, Beijing has witnessed a huge jump in its residential population from 4.2 million in 1949 to some 15 million today.
"It was mostly caused by the influx of non-native residents from all parts of China, including migrant workers, technicians and those employed by government and State-run organizations," the report said.
With such rapid economic and social progress, Beijing is expected to witness an even greater migration of people next year on the coattails of the Olympics and its many business and job opportunities, the report said.