A method and apparatus transmitting and receiving in a real-time system are disclosed. The method of transmitting in a real-time system includes scheduling a task included in a socket based on a predetermined transmission option designated to the socket, and transmitting a packet generated by the scheduled task based on the predetermined transmission option, so that real-time communications of a network communication can be secured and resources of the system can be efficiently used, thereby, transmitting and receiving data according to the required characteristics of transmission and reception.