In this study, polymeric sulfur and nanoclay were used as an asphalt binder modification approach with the aim of improving the rheological behavior of asphalt binder at high temperatures and enhancing its stability against aging. For this purpose, a base binder with a penetration grade of 85–100 was first modified with 30 wt% polymeric sulfur (commercial product: Googas), and then montmorillonite and bentonite nanoclays were incorporated into the modified binder at contents of 1, 2, and 3 wt%. The physical and rheological properties of the binders were evaluated through penetration, softening point, and dynamic shear rheometer (DSR) tests under unaged and short-term aged conditions. The results showed that the addition of Googas significantly increased the stiffness of the base binder and markedly improved its rutting resistance (G*/sin δ), raising the high-temperature performance grade (PG) from 58 to 70. Although incorporating nanoclays did not lead to a considerable change in the PG value, it reduced the aging index (AI) and enhanced the rheological stability of the sulfur-modified binder against short-term oxidation. The lower AI values observed in the nanoclay containing samples particularly those with montmorillonite indicate a reduced tendency toward hardening and better preservation of the binder structure during aging. Overall, the simultaneous use of polymeric sulfur and nanoclays can be considered an effective approach for improving high-temperature performance and enhancing the short-term aging resistance of binder in asphalt pavements