The invention discloses a TDD (Time Division Duplex) transmission method for a digital interphone. In the TDD transmission method, burst frames are used as base units to be transmitted. The TDD transmission method comprises the following steps: 1, entering a sending time slot of one burst frame, and in the sensing time slot, sending voice or data to a called terminal by a host terminal and simultaneously receiving the voice or the data sent by the host terminal by the called terminal; 2, entering a protection time slot of the burst frame, and in the protection time slot, switching a sending state of the host terminal into a receiving state and simultaneously switching a receiving state of the called terminal into a sending state; 3, entering a receiving time slot of the burst frame, and in the receiving time slot, sending voice or data to the host terminal by the called terminal and simultaneously receiving the voice or the data of the called terminal by the host terminal; and 4, after completing one burst period formed by the sending time slot, the protection time slot and the receiving time slot, starting to transmit the next burst frame and returning to the step 1 until the transmission of all voice or data is completed. According to the invention, the bidirectional communication can be completed at the same moment, so that both parties are enable to more smoothly communicate with each other.