Based on the Beijing panel data from 1990 to 2019, this paper expands the traditional Almost Ideal Demand System (AIDS) model by introducing the nutritional needs indicators by age structure and quantitatively analyzes the structure and characteristics of household food consumption in Beijing. The study estimates and compares the income elasticity, price elasticity, nutritional demand elasticity of food consumption structure, and the per capita food consumption in Beijing is predicted. The results show that commodity prices and income are still the key factors affecting consumer demand. The change in the population's age structure also has a corresponding impact on the consumption structure. The consumption structure of Beijing is in the stage of optimization, and relevant departments should formulate relevant policies to increase farmers' income and stabilize prices.