Abstract: An X-ray film marking device for selectively shielding X-ray film from X-rays so as to imprint identifying characters on the subsequently developed X-ray film. Lead indicia are supported by an X-ray transparent support sheet. The support sheet and therewith the indicia is releasably secured to any suitable structure between the X-ray source and film by a flexible pad having pressure-sensitive coatings of adhesive substances. A tab connected to the support sheet and of a predetermined color for easy association with a particular indicia allows for rapid removal of the marking device.