Food waste has caused double waste of resources in the food itself and the food supply chain of production, transportation, cooking, and processing, resulting in unnecessary greenhouse gas emissions and economic losses. This paper first conducted the quantification of students` food waste and the collection of canteens operation data in the three canteens at Taiyuan University of Technology (China) in 2019 through the weighing method and interview. Then an integration of Life Cycle Assessment and Life Cycle Costing was used to quantify the impact of food waste in university canteens on the environment and costs. The study found that the total amount of food waste in the university canteens with 22,000 students was 246.75 t/a, the carbon footprint caused by food waste was 539.28 t CO2-eq, and the cost was 4,729,900 yuan. Most of the impact of canteen meals on the environment comes from the use of energy in food cooking and the consumption of animal food types. The innovative integration of life cycle cost calculations highlights the key role of the labor required for cooking. The research results answer the basic scientific questions of how much food is wasted in the university canteens, and the carbon emissions and cost ratios of these wasted food in all links of the supply chain. The research results can provide a policy-making basis and data support for reducing food waste in universities and realizing carbon emission reduction in university canteens.