Embodiments of this application provide an information transmission method and apparatus. The method includes: receiving system information from a base station, wherein the system information comprises first configuration information, wherein the first configuration information is used to indicate a fixed-downlink time-frequency resource and a fixed-uplink time-frequency resource, or that a type of each unit time-frequency resource is not limited, and the type of the unit time-frequency resource comprises the unit time-frequency resource used to send uplink information, the unit time-frequency resource used to receive downlink information, or the unit time-frequency resource used to send uplink information and receive downlink information.