The computation of signatures is typically performed on physically insecure devices such as mobile phones or small IoT devices, which may lead to private key exposure and subsequently compromise the entire cryptographic system. Key-insulated signature schemes serve as a method to mitigate the damage caused by private key exposure. In a key-insulated cryptosystem, the public key remains constant throughout the entire time period, and the fixed private key is stored on a physically secure device. At the beginning of each time period, the insecure device interacts with the physically secure device storing the fixed private key to obtain the temporary private key for the current time slice. A secure identity-based key-insulated signature scheme must satisfy both unforgeability and key insulation. Key insulation ensures that even if an adversary obtains temporary private keys for multiple time periods, they cannot forge signatures for other periods. SM9 is a commercial identity-based cryptographic standard independently developed by China. This study applies the key-insulated method to the SM9 identity-based signature scheme to resolve the private key exposure issue present in the original scheme. First, a security model for identity-based key-insulated signatures is presented. Then, an identity-based key-insulated signature scheme based on SM9 is constructed. Finally, detailed security proofs and experimental analysis are provided.