A flashlight mounting system for a helmet of the type used by firefighters. The system has a light holder which is engageable with an adaptor on or secured to a helmet. A coupling is adjustable relative to the holder at engaging teeth and grooves to adjust the light and the path of the light beam. The adaptor and holder may be manually disengaged to change the orientation of the light or to allow the user to manually use the light and reattach the light in the original position without removing the helmet in dangerous environments and other environments.Inserts may be provided to adopt the light-receiving section to various styles, types and shapes of flashlights. The system allows the user to quickly adjust the flashlight and also allows the use of the light and holder with different helmets.