AbstractLarge size cerium (Ce3+)‐doped potassium chloride single crystal is grown by the resistance heating Czochralski method and characterized structurally, mechanically, and optically by carrying out X‐ray diffraction (XRD), micro‐hardness, photoluminescence (PL), PL excitation (PLE), thermo‐luminescence (TL), and decay time measurements. XRD measurements reveal the incorporation of Ce atoms into the KCl host lattice. Microhardness measurements indicate an improvement in the hardness due to Ce3+‐doping and a decrease of hardness with increasing temperature. Two intense PL emission peaks are observed at wavelengths 343 and 367 nm, attributed, respectively, to the 5d→2F5/2 and 5d→2F7/2 transitions of Ce3+. Energy level scheme for the Ce3+ ion in the KCl crystal is proposed through PL and PLE analyses. The observed TL glow curve of KCl:Ce3+ shows a sharp peak located at about 244 °C. XRD, PL, and TL studies confirm the trivalent state of Ce3+ ion in the KCl host lattice. The luminescence decay time of KCl:Ce3+ crystal is found to be 35.14 ± 0.17 ns. The present study indicates that the KCl:Ce3+ crystal grown exhibiting suitable PL and TL emissions is expected to be a potential material for radiation dosimetry and scintillation applications.