There is significant evidence that utilizing polymers improves asphalt cement characteristics, preserve the environment, and increases industrial-economic benefits. Consequently, the use of such modifier in asphalt cements via sustainable technology is strongly encouraged. The major goal of this research is to study the effect of modified asphalt cement with crumb rubber (CR) (10%, 15%, and 20% CR) and recycled polyethylene terephthalate (rPET) (1.5%, and 2.5% rPET) on the physical and rheological characteristics of asphalt cements. Asphalt cement experiments such as softening point, penetration, and rotational viscosity (RV), were performed on both the virgin and modified asphalt cements. The effect of CR and rPET on the temperature sensitivity of the asphalt cement was also evaluated by checking the penetration index (PI), penetration viscosity number (PVN), viscosity-temperature sensitivity (VTS), activation energy flow methods (AE) of all the modified asphalt cements. The rutting index (G*/sin δ) was calculated using Bari and Witczak model. The findings revealed that the addition of CR and rPET in the asphalt cement reduced the temperature sensitivity and enhanced the rheological characteristics of the asphalt cements. Moreover, incorporating the CR and rPET into virgin asphalt cements increased the high temperature performance of all percentage of CR and 2.5% WP modified asphalt. There was a considerable correlation between temperature sensitivity methods; PI, PVN, VTS, and AE. Finally, virgin asphalt modified with CR is better than rPET.