LuAG:Ce scintillators with excellent physical and scintillation properties have been widely utilized in radiation detection. However, three existing problems, such as Ce 3+ ions' selfabsorption effect, coupling-loss, and systems' radiation resistance, limit the LuAG:Ce scintillators' application. A couple-free LuAG:Ce-LuAG scintillating single crystal fiber (SSCF) for detection and transmission integrated performance was grown by the laser-heated pedestal growth method to address these. The Ce element along the growth direction of the as-grown LuAG:Ce-LuAG SSCF exhibits a three-segment distribution. The 1−1.5 cm length of LuAG:Ce detection segment for LuAG:Ce-LuAG SSCF is beneficial for enhancing the intensity of the output scintillation light at the collected end-face of the SSCF under X-ray or gammaray radiation. The thermal luminescence integrated intensity of LuAG:Ce SSCF still maintained 81% at 498 K and increased by 134% at 78 K compared to at room temperature. This design holds promise for the scintillation light strength collected from the transmission output end of the SSCF.