Embodiments provide a method and a device for transmitting downlink control information, where the method for transmitting downlink control information includes: determining, by a base station, duration information, where the duration information is used to indicate a duration that downlink control information to be sent from the base station to a user equipment needs to occupy; and sending, by the base station, the duration information to the user equipment, and sending the downlink control information to the user equipment in the duration, so that the user equipment receives the downlink control information according to the duration information.