A carrier indication method, user equipment, and a base station are disclosed. The method includes: receiving, by user equipment, first information sent by a base station; if the user equipment is capable of transmitting uplink data and downlink data on a carrier, determining, by the user equipment according to the first information, a carrier used for transmitting first-type information; and transmitting, by the user equipment, the first-type information on the determined carrier, where the first-type information includes at least one of the following: uplink data, downlink data, and scheduling information. In this application, user equipment determines, according to first information sent by a base station, a carrier used for transmitting information, and therefore, can normally transmit information.