The effect of mineral filler weight ratio on the low-temperature performance of hot asphalt mixtures with continuous gradation has been a subject of significant interest in the field of pavement engineering. This study focused on testing mastic, which is a bitumen mixture with mineral filler passing through a No. 200 sieve, using various tests such as the bending beam rheometer test, direct tensile test, Infrared spectroscopy test, X-ray diffraction test, and semi-circular bending test. Different weight ratios of mineral filler to useful bitumen ranging from 0.4 to 1.6 were investigated for PG 70-16 bitumen. According to the SHRP-A-407 standards, it was observed that the weight ratio of mineral filler to useful bitumen plays a crucial role in determining the low-temperature performance of the asphalt mixture. The research findings indicate that the weight ratio of mineral filler to bitumen plays a crucial role in determining the low-temperature performance of asphalt mixtures. As the filler-to-bitumen ratio increased, the stiffness of the bituminous mastic increased, leading to reduced fracture strain and decreased low-temperature cracking life. The optimal filler-to-bitumen ratio was recommended to be a maximum of 0.8 to balance performance and control low-temperature behavior. The results of this study underscore the importance of considering the rheological properties of bitumen mastic in addition to bitumen and asphalt mix when evaluating low-temperature performance.