Abstract: We make an in-depth analysis of the concept of resilient PNT (positioning, navigation, and timing) system put forward by the United States and China, and point out their differences.Especially in view of the main requirements of the future national comprehensive PNT system, the concept of resilience is expounded that the resilient index of the PNT system can be divided into three categories: external force interference characteristic, internal technical characteristic and performance effect characteristic.At the same time, considering the differences of different levels of PNT system design, PNT flexibility is divided into three levels: user-level resilience, system-level resilience and system-level resilience.Based on the above work, it tries to help promote the theoretical research in the field of PNT system in China.