Aiming at the problem that traditional quantum secure direct communication schemes need to assume thelegitimacy of both parties in advance, a GHZ state (a quantum state involving at least three subsystems orparticles entanglement) based quantum secure direct communication scheme with identity authentication isproposed. The scheme first encodes GHZ state particles into eight types, divides the particles into three parts,and sends them three times. Each time, eavesdropping is added to detect whether the particle detection channelis secure, and identity authentication is added when sending particles for the second time to verify the identityof the receiver. Specifically, according to the value of the ID key IDA, the specified particles (such as particles or particles) are found in the two particles. Then their positions are marked as L and they traversedown until all the identity keys are traversed, obtaining a position sequence L. After sending the two particlesto Bob for eavesdropping detection, Bob measures the L position of the two particles on the corresponding basisaccording to the value of the identity key, the measurement results are coded, and compared with the identitykey IDA to complete the identity authentication. After sending the particles for the third time. the receiverextracts all the detected particles, and then the GHZ state particles are jointly measured, and the originalinformation is recovered through the previously given coding rules, so as to realize quantum safe directcommunication. The design of this scheme is simple and efficient, and the communication can be realizedwithout complex unitary transformation. The correctness analysis proves that the scheme is correct in theory.The security analyses of interception/measurement retransmission attack, Trojan horse attack, denial of serviceattack, auxiliary particle attack, identity impersonation attack, and other attacks prove that the scheme canresist common internal attacks and external attacks, and solve the problem of information leakage. Thetransmission efficiency of the scheme is 1, the quantum bit utilization is 1, and the coding capacity is aquantum state carrying 3 bits of information. Compared with some previous schemes, this scheme has obviousadvantages in these three aspects. The biggest advantage is that the sender does not need to assume thelegitimacy of the receiver when sending information, so it has high practical application value
