A strobe lighting unit including a detecting circuit can reliably detect degradations of a xenon light source, which can flash as a light source for devices having a shooting with camera such as a smart phone, etc. The strobe lighting unit can include at least one xenon discharge tube as the xenon light source and at least one lighting circuit to flash the xenon discharge tube. The strobe lighting unit can also include at least one light-detecting circuit to detect degradations of the xenon discharge tube without a photo detector by monitoring an anode electrode of the xenon discharge tube at a flash thereof, and can be configured to output the monitoring result into the devices. Thus, the strobe lighting unit can result in an increase in the possible range of the devices, and can be employed for various devices including a thin mobile phone, a thin smart phone, etc.