<p>High-performance concrete (HPC) is increasingly being utilized in construction due to its improved qualities; however, its high cement content and low water-to-cement ratio cause significant heat generation during hydration, raising the danger of early-age thermal cracking. This study investigates the thermal cracking risk in HPC with varying levels of silica fume (SF) replacement (0%, 5%, 10%, and 15% by weight of cementitious materials). Experimental investigations were performed to determine the adiabatic temperature rise, compressive and cracking tensile strengths, and coefficient of thermal expansion of the four concrete mixtures. These experimental results were then used as input parameters for numerical simulations using the “EACTSA” program to assess temperature evolution, thermal stress development, and cracking potential in a representative bridge pier. The results indicate that while increasing SF content can accelerate early-age strength gain, its effect on thermal cracking risk is governed by the interaction between reduced thermal gradients and improved mechanical properties. SF replacement at 10% and 15% resulted in significantly lower cracking risk compared to 0% and 5%. This reduction reflects the combined effects of enhanced early-age tensile strength and reduced heat generation, with strength appearing more influential, although their relative contributions were not quantified and should be further investigated.</p>