The present disclosure relates to technologies for a sensor network, machine-to-machine (M2M) communication, machine type communication (MTC), and an Internet of Things (IoT) network. The present disclosure may be used in intelligence services based on such technologies (smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail business, and security and safety-related services). Provided is a method of transmitting encrypted data for preventing identification of transmitting and receiving devices, from a first device to a second device, the method including: generating an encryption key for encrypting data; generating key identification information by using the generated encryption key and encrypting the data; and transmitting a data set including the encrypted data and the key identification information to the second device.