A DCI sending method and an apparatus are provided. A base station determines a first channel resource, where the first channel resource is located in the ith time unit of a subframe in a time domain, the subframe includes NT time units, NT is an integer greater than or equal to 2, and i is a positive integer less than or equal to NT; and the base station sends DCI to a terminal device on the first channel resource. In this solution, the first channel resource that carries the DCI is located in the ith time unit of the subframe in the time domain, where i is a positive integer less than or equal to NT. That is, there is a first channel resource in each time unit of the subframe. Therefore, when data needs to be transmitted in any time unit, the data can be transmitted immediately.