A display apparatus, three-dimensional (3D) glasses, and a display system including the display apparatus and the 3D glasses are provided. The 3D glasses which interwork with an external display apparatus include: a wireless receiver which receives a sync signal and audio signals from the external display apparatus; a shutter driver which drives shutters according to the received sync signal; and an audio output part which processes and outputs the received audio signal. Thus, users can individually enjoy contents without interfering with one another by selecting and listening to audio corresponding to an image viewed through the display apparatus.