Abstract: To study the representation of high altitude electromagnetic pulse effect in communication network from a hierarchical perspective, a network-level effect assessment method with hierarchical feature was proposed. A network effect test and simulation platform for wireless network was designed and developed. The platform employs a typically fully-connected network, in which the communication node is designed based on the framework of superheterodyne transceivers with operating on very high frequency ranges. The effect of pulse irradiation test on this network platform was tested and its effect mechanism was analyzed. The influence of node failure probability on network performance under different network scales was studied by using OPNET software. The following conclusions are drawn: (1) The equipment-level effect has a certain redundant fault-tolerance for the lower-level damage effect, which depends on the selection of effect assessment indicators and the function properties of the damaged components; (2) The network-level effect has a potential effect on the equipment-level effect, and the failure of individual nodes may cause serious degradation or even paralysis of the whole network.