The sensing sensitivities of the Sr2InSbO6:Eu3+ phosphors with different doping concentrations were investigated based on the temperature-dependent decay curves. The crystal and electronic structure were studied by the X-ray diffractometer (XRD), Rietveld refinement, and X-ray photoelectron spectroscopy (XPS). In addition, the luminescent behaviors (e.g., photoluminescence spectra, concentration quenching, thermal stability, and luminescent dynamic) were investigated under the green light excitation (λex = 529 nm). The dominated peak was assigned to the 5D0 → 7F1 transition emitting an orange-red emission. Moreover, the obtained sample exhibited excellent thermal stability that the emission intensity remained 91.61% at 425 K. Eventually, the relative sensing sensitivity of the Sr2EuSbO6 phosphor was 0.766% K−1 and the doping concentration of Eu3+ ions greatly affected the sensing sensitivity. This work is the first time to investigate the single Eu3+-activated luminescent materials under the green light excitation.