The invention provides a data security authentication method between a cloud and an edge node, and the method provides a bidirectional identity authentication protocol between the edge node and the cloud, can guarantee the authenticity and effectiveness of the identities of the cloud and the edge node, prevents malicious attacks from permeating into a core network, and greatly guarantees the industrial Internet security. According to the method, an elliptic curve cryptographic algorithm is introduced to encrypt key data in an authentication process; the algorithm key size, the system parameters and the storage space are relatively small; operation speed is high, the highest safety intensity per bit is realized; the method is suitable for an authentication environment of edge computing nodes with limited computing resources and storage resources. According to the method, the data plaintext transmission leakage risk is avoided, the replay attack is avoided through the timestamp, the hashiterative operation of the one-time password authentication protocol is simplified, compared with the original authentication protocol, the security is higher, the operation efficiency is also improved, and the authentication security requirement can be met under the environment that the edge node resources are limited.