© 2019 Elsevier Ltd We developed three-dimensional (3D) dosimeters with radiophotoluminescence (RPL) material via fused-deposition modelling (FDM) 3D-printing technology. The 3D RPL dosimeter was a composite material consisting of polycaprolactone (PCL) resin and RPL glass. A filament having RPL characteristics was fabricated from the PCL resin and RPL glass with a filament-manufacturing machine for 3D printer. The RPL intensity of the filament showed good linearity with respect to the absorbed dose above 30 mGy. In a preliminary example, we printed 3D objects in the form of a ring and a human ear phantom, and the prototypes were irradiated with X-rays. By excitation of ultraviolet (UV) light, orange fluorescence was emitted from the X-ray irradiated parts. As a result, we succeeded in visually confirming dose information by ionizing radiation.