The purpose of this Article is to Designing a model for improving the Sustainable Performance of Small and Medium Food Companies in Guilan Province so that in the current environment, managers and decision makers by recognizing the factors, challenges and consequences to improve the sustainable performance of Small and Medium Food Companies. The present Article is in the category of applied research from the perspective of purpose, in the category of exploratory-descriptive research in terms of nature and in the field of field studies based on data collection.This Article is in the category of qualitative research. A paradigm model was created by the Grounded theory method through three stages of open, axial and selective coding. The Results of data Analysis using Grounded Theory led to the formation of 13 main floors, 29 main categories and 248 concepts. The six main classes of paradigm model of the Grounded theory using theoretical coding in the form of: pivotal phenomenon (sustainable performance improvement), causal conditions (organizational survival, social and environmental obligation, gaining competitive advantage), contextual conditions (environmental factors, organizational factors), Interfering Conditions (environmental factors, organizational factors), strategies (macro level, organizational level). Finally the Economic, Social and Environmental consequences of achieving Sustainable Performance Improvement were achieved by implementing the strategies.