According to experts, China's migrant population could reach the 310-million mark by 2030, however, at lower pace, ultimately leading to fewer number of laborers.
The country had 254 million migrants as of last year.
National Health and Family Planning Commission (NHFPC) deputy head Wang Peian stated that in 15 years, 230 million rural residents are also expected to move to the cities.
Earlier in the 1990s, millions of migrants have left their rural homes for work in China's booming urban areas such as Beijing, Guangzhou and Shanghai.
Furthermore, Wang predicts that there will be a sustainable rise in the number of migrant laborers in the coming years. The 2010 census shows that migrants have a 16.2-percent share in the national population.
Wang said that coastal and metropolitan cities in Southeast China will continue to be attractive to migrants. Moreover, due to the "One Belt, One Road" initiative, more of them will opt to work in cities near their hometowns.
However, he remarked that the growth rate will taper off, citing that between 2010 and 2015, there was an eight-million increase but the number will be decreasing by a quarter in the next five years.
Zhuang Ya'er, a China Population and Development Research Center research fellow, said that the decline could be partly attributed to the lower fertility rate.
Zhuang's forecast is that there will be fewer laborers, given the country's family planning control policy.
According to People's Daily, China's average fertility rate last year was 1.6 births per woman, lower than the 2.1 global standard, which prevents a population from shrinking.