Based on the research of knowledge management and knowledge flow, this paper take the factors which influences the flow of knowledge among the enterprises as the mainly research objects. It uses the Knowledge Absorptive Capacity, Knowledge Matching Degree, Industry Openness Degree as the total input, Knowledge Flow Effects as the total output. Using survey data for example design, and using Rough Sets Theory method calculating and analysis the data. Through the upper approximation and lower approximation describing the relationship between the totle input and knowledge flow effects. Then provide a meaningful guidance for knowledge flow smoothly in the supply chain, enhancing the overall knowledge ability,and improve efficiency and knowledge ultimately benefit.