Embodiments provide an information transmission method and a device. The method includes: determining, by a first device, a subcarrier spacing of a serving cell; determining a resource unit of the serving cell based on the subcarrier spacing of the serving cell; and sending information to a second device in the serving cell based on the resource unit of the serving cell, or receiving, in the serving cell based on the resource unit of the serving cell, information sent by the second device. In this way, information transmission is implemented based on a plurality of sets of system parameters.