Voice service method and device based on different network roaming

The invention relates to a voice service method and device based on different network roaming, and a computer readable storage medium, and relates to the technical field of communication. The voice service method based on different network roaming is executed by a visited 5G network, and comprises the following steps: in response to a 5G terminal accessing or switching into the visited 5G network, judging whether the 5G terminal belongs to a roaming terminal; under the condition that the 5G terminal belongs to a roaming terminal, judging whether the 5G terminal supports a voice over noise ratio (VONR) of a new air interface; and under the condition that the 5G terminal does not support the VORR, controlling the 5G terminal to access a home 4G network, so that the 5G terminal obtains a voice service in a roaming area. According to the invention, the 5G terminal which does not support the VORR can obtain the voice service in the roaming area, and the voice service quality in a different-network roaming scene is