A time-delayed temperature sensing method based on a fluorescence decay profile was proposed for the purpose of boosting the temperature sensitivity of optical thermometry. The thermal quenching effect of the LiCa3ZnV3O12 sample was investigated to evaluate the viability of the method. Specifically, by applying the integral intensity obtained after a certain delay time in the normalized decay profile as a probing parameter, high relative sensitivity with a maximum of 13.5% K−1 was achieved. The high relative sensitivity along with the good reversibility verified by the temperature cycling test indicate that the time-delayed sensing strategy proposed here is promising for excellent optical thermometry.