The invention discloses an industrial internet data encryption transmission method based on a stream cipher, which is used for realizing data encryption transmission between a sender and a receiver in an industrial internet. The method comprises the following steps: a sender sends data to be sent to an encryption gateway; the encryption gateway generates a unique identifier, calculates a stream key index used for encrypting current data based on the identifier, extracts a stream key from a stream key sequence according to the stream key index, encrypts the current data by using the stream key, and then sends the identifier and ciphertext data to a decryption gateway of a receiver together; and the decryption gateway firstly extracts data identification information, then calculates a stream key index for decrypting the current ciphertext based on the identification, extracts a stream key from a stream key sequence according to the stream key index, decrypts the current ciphertext by using the stream key, and finally sends the obtained plaintext data to a receiver. According to the data encryption transmission method, correct transmission of the data can be ensured, the calculation amount of encryption and decryption is reduced, and the data transmission efficiency is improved.