Abstract: Unmanned Aerial Vehicle Group Network （UAVGN） has dynamic topology and high mobility, so it is easy to suffer security threats and attacks in the open air wireless environment. Especially the communication transmission link is prone to interference, and the communication is unstable or even is interrupted, leading to the loss of key packets in the process of key management, so that the subsequent session cannot establish key secure communication. Therefore, considering the limited UAV resources, this paper proposes a healing group key management scheme based on Hash chain and Chinese residual theorem, which has two mechanisms of self-healing and mutual healing, and improves the flexibility and efficiency of UAV key updating. Meanwhile, group key update is divided into local update key and session update key. The local update key is updated locally by the preset Hash function, which further reduces the calculation overhead of key update and improves the key processing capability of UAV. The Key Group Manager （KGM） selects the Key update factor in the session stage, constructs the broadcast message of key update by using the Chinese Remainder Theorem （CRT）, and realizes the dynamic and flexible update of key. The analysis and experiment show that the scheme has security performance such as forward security, backward security, anti-undo ability, anti-collusion attack and anti-replay attack. Compared with the existing schemes under the same conditions, this paper effectively optimizes the computation and communication overhead, improves the key update efficiency, and can solve the key update problem in the unstable communication of UAVGN, thus ensuring the establishment of secure key communication.

Key words: UAVGN, healing, key management, key update, hash function, Chinese remainder theorem