Embodiments of this application provide a blind detection method. A terminal side device receives first indication information from a network side device, where the first indication information is used to determine at least one of N time units, a first time unit in the N time units corresponds to a type of terminal operation, the terminal operation is not performing a first operation, a second operation, and a third operation, the N time units belong to a same transmission time unit, and any one of the N time units includes at least one symbol, where N is an integer greater than 0. The terminal side device determines the N time units based on the first indication information, and performs the corresponding terminal operation in the first time unit in the N time units.