A base station, comprising: a sending module, configured to send system information of the base station to user equipment at a frequency of the base station, to trigger the user equipment to access the base station according to the system information of the base station; a receiving module, configured to receive identifiers of coverage base stations that cover the user equipment and access capability information of the user equipment that are sent by the user equipment, wherein the access capability information is used to indicate a target frequency band that the user equipment is allowed to access, and the target frequency band is different from a frequency band in which the frequency of the base station is located; and a determining module, configured to determine, from the coverage base stations and according to the target frequency band, one or more target base stations whose frequencies are located in the target frequency band, wherein the sending module is further configured to send system information of the one or more target base stations to the user equipment, to trigger the user equipment to select system information of one target base station from the system information of the one or more target base stations as system information of a target access base station, and access the target access base station according to the system information of the target access base station, wherein a structure of the system information of the base station comprises one master information block and multiple system information blocks, wherein the master information block is used to broadcast state information of the base station, and the system information blocks are used to broadcast access information required by the user equipment for accessing the base station, and a structure of the system information of the one or more target base stations comprises one master information block and multiple system information blocks, wherein the master information block is used to broadcast state information of the one or more target base stations, and the system information blocks are used to broadcast access information required by the user equipment for accessing the one or more target base stations, and wherein the target frequency band that is different from a frequency band in which the frequency of the base station is located, comprises: when a bandwidth of the frequency band in which the base station is located is between 300 MHz and 6 GHz, a bandwidth of the target frequency band is between 30 GHz and 300 GHz; or when a bandwidth of the frequency band in which the base station is located is between 30 GHz and 300 GHz, a bandwidth of the target frequency band is between 300 MHz and 6 GHz. a sending module, configured to send system information of the base station to user equipment at a frequency of the base station, to trigger the user equipment to access the base station according to the system information of the base station; a receiving module, configured to receive identifiers of coverage base stations that cover the user equipment and access capability information of the user equipment that are sent by the user equipment, wherein the access capability information is used to indicate a target frequency band that the user equipment is allowed to access, and the target frequency band is different from a frequency band in which the frequency of the base station is located; and a determining module, configured to determine, from the coverage base stations and according to the target frequency band, one or more target base stations whose frequencies are located in the target frequency band, wherein the sending module is further configured to send system information of the one or more target base stations to the user equipment, to trigger the user equipment to select system information of one target base station from the system information of the one or more target base stations as system information of a target access base station, and access the target access base station according to the system information of the target access base station, wherein a structure of the system information of the base station comprises one master information block and multiple system information blocks, wherein the master information block is used to broadcast state information of the base station, and the system information blocks are used to broadcast access information required by the user equipment for accessing the base station, and a structure of the system information of the one or more target base stations comprises one master information block and multiple system information blocks, wherein the master information block is used to broadcast state information of the one or more target base stations, and the system information blocks are used to broadcast access information required by the user equipment for accessing the one or more target base stations, and wherein the target frequency band that is different from a frequency band in which the frequency of the base station is located, comprises: when a bandwidth of the frequency band in which the base station is located is between 300 MHz and 6 GHz, a bandwidth of the target frequency band is between 30 GHz and 300 GHz; or when a bandwidth of the frequency band in which the base station is located is between 30 GHz and 300 GHz, a bandwidth of the target frequency band is between 300 MHz and 6 GHz.