A method of performing D2D (device-to-device) relay communication, which is performed by a user equipment (UE) in a wireless communication system according to various embodiments, and an apparatus are disclosed in the present invention. The method includes the steps of receiving information on a relay probability corresponding to a probability for performing relaying, receiving a message to be relayed, determining whether to perform relaying on the received message based on the information on the relay probability, and if it is determined to perform relaying, transmitting the message.