The direct anonymous attestation (DAA) scheme is a promising authentication scheme in a single trust domain. However, the existing schemes fail to effectively solve the problem of mutual authentication of vehicle nodes between different trust domains. This paper designs a cross-domain remote DAA scheme combined with a mimic defense mechanism (CD-DAA-MD) for the Internet of Vehicles (IoV). Specifically, the trust chain is constructed, and the mimic defense mechanism is combined with a trusted auditor (TA) to meet the urgent needs of the security of the IoV. Furthermore, a dynamic heterogeneous redundancy structure (DHR) composed of multiple heterogeneous executors is established, where the heterogeneous redundancy between each heterogeneous executor is applied to effectively enhance the security of the TA and simultaneously strengthen the trustworthiness of the TA’s identity when participating in the cross-domain link We analogize the proof method that combines the random oracle model and the protocol judgment to evaluate the security issues at the protocol level, where a model based on the probability of heterogeneous executors being compromised is utilized. Simulation results show that our scheme effectively reduces the communication overhead without compromising security. The communication overheads of the TA-Join protocol in our scheme are reduced by about 15% compared with existing schemes. The efficiency of completing the entire cross-domain interactive authentication process is nearly 25% higher than the existing schemes.