After 2000，China initially completed its demographic transition and entered apost-demographic transition period characterized by a continuous shift in population age and urban-rural structure．The rapid economic growth of China has led to great changes in consumption; the expansion of consumption scale has also become the main driving force of economic growth．However，the study on the impact of the change of population size，structure and spatial distribution on consumption structure in new period is scarce． Based on the three waves of the China Family Panel Survey (CFPS) from 2012 to 2016，this paper uses Dirichlet proportional regression model to explore the impact of house hold demographics on household consumption pattern and the difference of the relationship between the two various years and regions．The results show that when income level is controlled, household demographic characteristics play an important role in the change of consumption pattern．Overall， the difference between urban and rural areas and urbanization process have played a significant role．The expansion of national consumption mainly comes from cities，while the change of consumption structure mainly lies in rural areas．In terms of the relationship between demographics and consumption structure, the age of the householder has U-shape relationships with the proportion of housing，medical care，transportation ＆ communication，culture ＆ education ＆ entertainment; but its impact on the proportion of daily necessities and clothing expenditure shows an inverted U-shaped relationship．Larger，more educated and female-headed households spend a large proportion of their non-food consumption. From the perspective of regional difference，the proportion of food expenditure in the central and western regions is lower than that in the eastern region, but the relationship between household demographic characteristics and consumption structure is basically stable in different regions．From the longitudinal perspective，the study also found that the differences in consumption structure between urban and rural households kept expanding over time, while the situation that the proportion of non-food consumption expenditure of the families with higher education level and female head of household is high weakens to some extent．
