A road traffic control system includes a mobile terminal, a fixed terminal, a traffic sign, a control module, and a prompt unit. The mobile terminal includes a mobile terminal communication module for transmitting mobile terminal parameter data. The fixed terminal includes a fixed terminal communication module that is in communication connection with the mobile terminal communication module and is configured to receive the mobile terminal parameter data. The traffic sign includes a sign communication module configured to be in communication connection with the fixed terminal communication module. The control module is connected to the sign communication module. The prompt unit is connected to the control module and configured to provide a traffic instruction according to the mobile terminal parameter data.