Abstract Scintillation and dosimetric properties of a LiF/CaF 2 :Dy eutectic composite have been studied. In the X-ray induced emission spectrum and decay curve, we observed luminescence due to self-trapped exciton of CaF 2 and 4f–4f transitions of Dy 3+ ions. The LiF/CaF 2 :Dy eutectic composite showed the light yield of 3000 photons/neutron as a neutron scintillator. The LiF/CaF 2 :Dy eutectic composite showed the measurable range from 1 mGy to 10 Gy as a thermoluminescence dosimetric material. The LiF/CaF 2 :Dy eutectic composite can act as a dual functional material for neutron detection and X-ray dosimetry.