Abstract: An apparatus and method for transmitting and receiving a signal between different networks, each network having at least one terminal and a different source coding method and transmission rate from those of the other network. The apparatus for transmitting and receiving a signal between different networks includes: a system controller, responsive to a call setup request signal, for inquiring a second coding method used for a second terminal in a second network and informing a first terminal of the second coding method; a data encoder for encoding data signals from the first terminal in accordance with the second coding method; a matcher for changing a transmission rate and a data format of encoded data signals to a transmission rate used in the second network; and a decoder for decoding data signals from the matcher.