A method for transmitting multicarrier-supported capability of User Equipment, UE, comprising: sending out, by UE, a message carrying multicarrier-supported capability of the UE, when the UE supports multicarrier; parsing, by an RNC, the message carrying multicarrier-supported capability of UE received from the UE; and obtaining the multicarrier-supported capability of the UE; wherein after the RNC obtains the multicarrier-supported capability of the UE, deciding, by the RNC, that a service is received by a multicarrier cell, wherein the deciding comprises: carrying, by the RNC, auxiliary carrier cell information in a radio link setup request message or in a radio link reconfiguration request message which is sent to a NodeB, and carrying the auxiliary carrier cell information in a radio bearer setup message or in a radio bearer reconfiguration message which is sent to the UE; wherein the multicarrier-supported capability is the capability that a number of the carriers received by UE simultaneously is more than 2; characterized by the step of sending out, by the UE, the message carrying the multicarrier-supported capability of the UE comprises: expanding a level of a High Speed-Downlink Shared Channel, HS-DSCH, physical layer category to add a level of the multicarrier-supported capability of the UE; and sending out an RRC connection setup complete message or a UE capability information message carrying the expanded HS-DSCH physical layer category when the UE supports multicarrier. sending out, by UE, a message carrying multicarrier-supported capability of the UE, when the UE supports multicarrier; parsing, by an RNC, the message carrying multicarrier-supported capability of UE received from the UE; and obtaining the multicarrier-supported capability of the UE; wherein after the RNC obtains the multicarrier-supported capability of the UE, deciding, by the RNC, that a service is received by a multicarrier cell, wherein the deciding comprises: carrying, by the RNC, auxiliary carrier cell information in a radio link setup request message or in a radio link reconfiguration request message which is sent to a NodeB, and carrying the auxiliary carrier cell information in a radio bearer setup message or in a radio bearer reconfiguration message which is sent to the UE; wherein the multicarrier-supported capability is the capability that a number of the carriers received by UE simultaneously is more than 2; carrying, by the RNC, auxiliary carrier cell information in a radio link setup request message or in a radio link reconfiguration request message which is sent to a NodeB, and carrying the auxiliary carrier cell information in a radio bearer setup message or in a radio bearer reconfiguration message which is sent to the UE; wherein the multicarrier-supported capability is the capability that a number of the carriers received by UE simultaneously is more than 2; expanding a level of a High Speed-Downlink Shared Channel, HS-DSCH, physical layer category to add a level of the multicarrier-supported capability of the UE; and sending out an RRC connection setup complete message or a UE capability information message carrying the expanded HS-DSCH physical layer category when the UE supports multicarrier.