Currently, the topic of food waste and its environmental impacts is attracting increasing attention among academic researchers. Based on an investigation of restaurants in Beijing, this study analyzes the quantities, structures, characteristics and costs of the agricultural resources related to food waste in the catering industry in Beijing. The results show that: (1) The average food waste per capita per meal is about 75.02 g (raw) for food away from home among Beijing urban residents, which means that about 10.52% of the food is wasted. (2) According to the quantitative ranking of different categories of food waste, vegetable is the most wasted, followed by meat, aquatic products, and grains. The foods in the other categories are wasted much less. (3) Food waste is affected by the restaurant type, as well as the number, gender, age, education level, and consumption motivation of the consumers. (4) Based on the estimated food waste per capita, about 417.92 thousand tons of food is wasted annually at the consumption stage in the catering industry in Beijing. This food waste amount is equivalent to approximately 765.53 tons of cereals which are wasted, and this represents 79.66% of cereals production and 13.15% of cereals consumption in Beijing. Estimated by the required land use, this amount of food waste means that the total production of approximately 166.12 thousand ha of arable land is being wasted in Beijing.