An object-based 3-D audio system. An audio input unit receives object-based sound sources. An audio editing/producing unit converts the sound sources into 3-D audio scene information. An audio encoding unit encodes 3-D information and object signals of the 3-D audio scene to transmit them through a medium. An audio decoding unit receives the encoded data through the medium, and decodes the same. An audio scene-synthesizing unit selectively synthesizes the object signals and 3-D information into a 3-D audio scene. A user control unit outputs a control signal according to the user's selection so as to selectively synthesize the audio scene by the audio scene synthesizing unit. An audio reproducing unit reproduces the audio scene synthesized by the audio scene-synthesizing unit.