A data transmission method is provided. The method includes: receiving, by user equipment, first information from a radio access device, where the first information indicates different transmission classes corresponding to a plurality of logical channels; determining, by the user equipment based on the first information, a transmission format of uplink data on at least one logical channel corresponding to at least one transmission class in the different transmission classes, and determining a transmission resource in the transmission format; and sending, by the user equipment, the uplink data by using the transmission format and the transmission resource in the transmission format. In this application, different transmission resources are allocated to uplink data on logical channels (LCHs) of different transmission classes, so that different requirements of different uplink data can be met.