As residents attach more and more importance to healthy diet, the catering problem has garnered widespread public attention. Nutrient-based dietary planning can give viable dietary recommendations for the above problems. In this paper, this study establishes a dietary planning model to find the minimum dietary expenditure under the condition that the daily nutritional requirements of diabetic patients are met and the upper limit of nutrient intake is not exceeded. Employing a dependable mathematical model, we make viable planning for diverse social groups and varied food materials, so as to give viable recommendations to the greatest extent.