Shear-thickening fluids, as innovative smart materials that respond promptly to external impact loads, are increasingly attracting widespread attention within both the academic and industrial sectors. An in-depth investigation of their dynamic response characteristics under transient loading conditions and the underlying mechanisms offers significant scientific importance and practical value for expanding their potential applications in various high-performance settings. This article focuses on the study of silicone rubber-based shear-thickening fluids and their composites, which have demonstrated considerable potential in industrial applications. Specifically, this research utilizes typical shear-thickening fluids made from silicone rubber and explores the behavior of these materials under varying stress conditions by incorporating various hard particulates to create composites. Through meticulously designed experiments using a modified Hopkinson pressure bar and quasi-static testing with an Electro-mechanical universal machine, this study successfully obtained stress-strain curves across a broad range of strain rates. Comparative analyses indicate that the stress levels in these materials increase with the strain rate and that the reinforcement effect is more pronounced with an increase in the content of hard particles. Additionally, this paper conducts a detailed theoretical exploration and simulation analysis using a unit cell model to investigate the mechanisms behind the strength enhancements following the incorporation of hard particulates, further elucidating the microstructural reinforcement mechanisms.