A dimming control device is configured to be electrically connected to a pull switch for controlling a lighting device. The dimming control device includes a control module and a power module. The control module is configured to be electrically connected to the pull switch for receiving a trigger signal that is indicative of a pulled duration for which a cord of the pull switch is pulled and held in a pulled state. The power module is controlled by the control module according to the trigger signal to operate the lighting device by turning on/off lighting elements of the lighting device, or steplessly adjusting brightness of light emitted from any lighting element that is turned on.