Abstract: In the view of breeding profit of layer and food safety， a causality diagram of “the general scale farming” and “company and farm” was constructed by using system dynamics model. Then the operation characteristics of supply chain of two kinds of layer breeding mode were analyzed， the system dynamics model of layer was built， and the system simulation was carried out， and the profit and food safety of two types of layer breeding mode were compared and analyzed. The results showed that the “company and farm” mode is a good mode from the perspective of ensuring the food safety and increase benefits of farmers， and the relative countermeasures and suggestions were proposed.

Key words: layer, general scale farming, “company and farm”, system dynamics