Embodiments of this application provide a control channel configuration method, a base station, and a terminal device. The method includes: determining, by a base station, a configuration of a time-frequency resource unit from at least two configurations of a time-frequency resource unit of a control channel; and sending, by the base station, indication information to a terminal device, where the indication information is used to indicate the configuration of the time-frequency resource unit, and the at least two configurations of a time-frequency resource unit include a first configuration and a second configuration. In the embodiments of this application, the base station can flexibly configure the time-frequency resource unit of the control channel. In addition, flexibly configuring a time-frequency resource unit can reduce a probability that time-frequency resource units of different structures are blocked, thereby reducing complexity of detecting the control channel by the terminal device.