A physical resource block PRB grid indication method and a device are disclosed. The method includes: receiving, by a terminal device, location information sent by a network device, where the location information is used to indicate a relative location relationship between a first predetermined location in a synchronization signal block PRB grid and any PRB in a system common PRB grid with a first subcarrier spacing; and determining, by the terminal device, a second predetermined location of the any PRB based on the first predetermined location and the location information.