在推动经济高质量发展过程中，刺激消费、扩大内需是形成国内大循环主体的重要路径。文章借助2018年中国家庭追踪调查数据和2019年《中国统计年鉴》数据，运用分层线性模型实证分析中国家庭人口规模对家庭人均消费的影响。研究表明：其他条件不变时，家庭人口规模扩大对人均消费增加有抑制作用；地区差异影响了家庭人口规模对人均消费的抑制作用；城镇化率、人均地区生产总值、人均地方社会保障支出在家庭人口规模对家庭人均消费的影响中有调节作用。今后应进一步完善收入再分配制度，提高个人受教育水平，推动城镇化进程，助力实现高质量发展。

In the process of promoting high-quality economic development, stimulating consumption and expanding domestic demand is an important way to form the main body of domestic circulation. Based on the data of 2018 Chinese Household Tracking Survey and 2019 Chinese Statistical Yearbook, this paper empirically analyzes the impact of family size on per capita household consumption in China using a hierarchical linear model. The study finds that the increase of family size has a restraining effect on per capita household consumption; regional differences affect the inhibiting effect of family size on per capita consumption, accounting for 14.39% of the variation of total per capita consumption; at the regional level, urbanization rate, per capita GDP and social security level have a moderating effect on the size of family population, which then affects the per capita consumption level. It is of great necessity to further perfect income redistribution system, improve level of education and promote the process of urbanization to help to achieve the high-quality development.