As an important infrastructure system, civil aviation network system can be severely affected by natural hazards. Although a natural hazard is usually local, its impact, through the network topology, can become global. Inspired by Wilkinson’s work in 2012, this article proposes a new quantitative spatial vulnerability model for network systems, which emphasizes the spreading impact of spatially localized hazards on these systems. This model considers hazard location and area covered by a hazard, and spatially spreading impact of the hazard (including direct impact and indirect impact through network topology) and proposes an absolute spatial vulnerability index and a relative spatial vulnerability index to reflect the vulnerability of a network system to local hazards. The model is then applied to study the spatial vulnerability of the Chinese civil aviation network system. The simulation results show that (1) the proposed model is effective and useful to study spatial vulnerability of civil aviation network systems as the results well explain the general situation of the Chinese civil aviation system; and (2) the Chinese civil aviation network system is highly vulnerable to local hazards when indirect impacts through network connections are considered.@en