This application provides a control information transmission method, a base station, and a terminal. The method includes: extracting a radio resource from a preset resource block set, and sending control information in a first time period by using the radio resource. The base station includes a processor and a transmitter. The processor is configured to extract a radio resource from a preset resource block set, and the transmitter is configured to send control information in a first time period by using the radio resource. According to the control information transmission method provided in this application, the base station can send the control information in any time period, and the terminal can receive the control information in any time period, thereby shortening a time interval between two control information transmissions.