Provided are a method and device for transmitting information, a base station and user equipment (UE). The method can include determining supplemental system control information for target UE to communicate in an unlicensed spectrum, the supplemental system control information being configured to inform the target UE of configuration information of a supplemental bandwidth part (SBWP) allocated in the unlicensed spectrum. The method can further include sending the supplemental system control information to the target UE through a primary BWP that is allocated in a licensed spectrum by the base station to the target UE, and scheduling the target UE on the primary BWP and the SBWP to perform information transmission. The method for transmitting information provided by the present disclosure may achieve flexible scheduling of unlicensed spectrum resources in a licensed spectrum, as well as improve the configuration flexibility and effective utilization of the unlicensed spectrum resources.