SpaceWire is the new space bus standard proposed by ESA, which has been successfully applied in many projects. Delay jitter is the key parameter to reflect the network transmission performance, which measures the difference between the maximum transmission delay and the minimum transmission delay from end to end. Through theoretical calculations and modeling simulations, a quantitative analysis and research for the delay jitter of the SpaceWire under specific application scenarios was carried out. Theoretical calculations obtained the delay jitter under particular scenarios by theoretical derivation. Modeling simulations, on the other hand, established simulation model by Opnet, and obtained the maximum transmission delay and minimum transmission delay by simulation. In this way, the delay jitter was calculated both qualitatively and quantitatively, and the parameters which have key impact on delay jitter were obtained. Recommendations and methods to improve the delay jitter were given by analyzing the conclusions. The research results of this article can provide a reference for the SpaceWire design to build a low delay jitter SpaceWire network.