Aiming at the phenomenon of bottleneck shifting in job shop, this article presents the findings on the coupling relationship among the bottleneck shifting factors. We first defined the chain probability to show the relation that the change of one bottleneck shifting factor causes the changes of other factors in job shop. Then, we used three variables (time-capability, time-load, and quality-assurance) and the transaction probability to describe the changes of the factors. Considering the interaction among the bottleneck shifting factors, we established the independent contributions and comprehensive contributions, showing how the changes of various shifting factors may impact the bottleneck shifting phenomenon interactively. Finally, an instance of analysis of the coupling relation of several bottleneck shifting factors in some job shop is given to test the validity and rationality of the method established in this research.