Abstract: An apparatus and method for enhancing speech quality in digital communications. In the speech-quality enhancing apparatus, an input buffer stores a sum signal of a first input signal to be transmitted and an echo signal generated from a received second input signal at a predetermined time interval. An echo canceller receives the sum signal based on a unit of a buffer from the input buffer, cancels the echo signal from the sum signal, and outputs the first input signal. A noise canceller receives the first input signal based on the buffer unit from the echo canceller, and cancels a noise from the first input signal. A level controller receives the first input signal based on the buffer unit from the noise canceller, and adjusts a level of the first input signal. A speech compression module receives the first input signal based on the buffer unit from the level controller, converts the first input signal into a digital signal, and compresses the digital signal.