A method and a device for configuring a central subcarrier are disclosed. The method comprises: mapping a first downlink control channel onto a part (f1) of a downlink bandwidth (fW) of a cell, and configuring a first virtual central subcarrier in f1, where f1 is different or partly different from a bandwidth f2 mapped to a second downlink control channel, an overlap between f1 and f2 is at least one subcarrier, or at least one idle subcarrier exists between f1 and f2, or at least one non-idle subcarrier and at least one idle subcarrier exist between f1 and f2; the first virtual central subcarrier is located on a grid position of a central frequency, a distance between the first virtual central subcarrier and a second virtual central subcarrier configured in f2 is an integer multiple of a frequency domain width of the subcarrier.