The Ministry of Civil Affairs will conduct a census of left-behind children in 2016, a senior official said.
Ni Chunxia, deputy director of the ministry's Department of Social Affairs, said it will be the first national-level census of left-behind children.
Song Yinghui, a law professor at Beijing Normal University, said China has about 100 million children from migrant workers' families, more than 60 million who were left behind in their hometown, and more than 36 million travel with their migrant worker parents.
"The number－100 million－is about one-third of Chinese children under 18, which means that one in three children in China is left-behind or travels with parents," Song said, adding that this presents a challenge to social administration.
The number of left-behind children in China has never been agreed upon.
"One number is about 60 million, and the other is about 80 million," said Wan Guowei, associate professor specializing in public administration at Lanzhou University, adding that the difference comes from the absence of both parents or only one parent.
The last survey of left-behind children by an authoritative organization was done by the All-China Women's Federation in 2013, which estimated that China had about 61.02 million left-behind children.
With rapid urbanization over the last two decades, millions of migrant workers have moved to cities, leaving their children at home.
A 2015 survey conducted by Shangxuelushang, an NGO that helps left-behind children, said about 15 percent of them reported having no physical contact with their parents during the course of a calendar year.
Four percent received just one phone call a year from parents, it said.
The neglect caused some tragedies. In June, four siblings aged 5 to 13 who had been left behind in Bijie, Guizhou province, committed suicide by drinking pesticide at home.
"Left-behind children's tragedies may hit the front pages of newspapers for a few days, but when the stories go cold, people's attention shifts. The key to solving the problem is to establish a system to help them and prevent such tragedies," said Liu Wenkui, secretary-general of the China Foundation for Poverty Alleviation.
The central government is taking action to establish a system to address the plight of left-behind children. A guideline for their protection was signed by Premier Li Keqiang and released in February.
The comprehensive survey of left-behind children will be carried out by the Ministry of Civil Affairs and other government organs, such as the Ministry of Education and the Ministry of Public Security, according to Vice-Minister of Civil Affairs Zou Ming at a State Council Information Office media briefing in February.
A new section to protect left-behind children in rural areas was set up by the Ministry of Civil Affairs in February.
"The section will effectively link social assistance, welfare and other resources and also work to link government organs to improve a whole system to protect left-behind children," the ministry's Department of Social Affairs said.
The section will carry out the census.
