Since 2000,the structural changes of China's youth population have mainly been reflected in:the inertia reduction in quantity and proportion;the exacerbation of gender imbalance bringing difficulties to youth marriage and other social risks;up-graded scientific and cultural literacy promoting high-quality development of population and economy but creating new problems in the structure of health;diversified distribution of employment industry structure but still insufficient development and utiliza-tion of human and talent resources;free mobility bringing about redistribution of young people between regions and between ur-ban and rural areas,promoting urban development,but also increasing the imbalance risk of regional development;obvious trend of delayed marriage and childbirth,growing proportion of unmarried and infertile individuals,increased number of young people living alone with prolonged period of time,and increased risk of individual atomization among young people.Among them,the reduction in the number and proportion of young people is mainly caused by the iteration of the population age structure itself.Because of persistent low fertility levels,the number of births in each generation is decreasing,leading to a vicious cycle of low fertility and birth decline in China.The policy recommendations for addressing these issues are to tilt resources towards vocation-al education,guide for healthy and balanced flow of talents,and build friendly environment for maternal and child health care.