A data processing method is provided. A terminal device encrypts a target instruction and a first identifier using a first key to obtain a first ciphertext; and sends the first ciphertext to an IoT device through an IoT platform. The IoT device decrypts the first ciphertext using a second key to obtain the target instruction and the first identifier; determines whether the first identifier matches a second identifier stored locally and comes to a matching result, the first key and the second key being negotiated by the terminal device and the IoT device; and obtains a second cipher text by encrypting the matching result using the second key. The terminal device receives the second ciphertext returned by the IoT device through the IoT platform; decrypts the second ciphertext using the first key to obtain a decryption result; and performs a corresponding operation using the decryption result.