Rocket sleds belong to a category of large-scale test platforms running on the ground. The applications can be found in many fields, such as aerospace engineering, conventional weapons, and civil high-tech products. In the present work, shock-wave/rail-fasteners interaction is investigated numerically when the rocket sled is in supersonic flow conditions. Two typical rocket sled models are considered, i.e., an anti-D shaped version of the rocket sled and an axisymmetric slender-body variant. The dynamics for Mach number 2 have been simulated in the framework of a dynamic mesh method. The emerging shock waves can be categorized as head-shock, tailing-shock and reflected-shock. An unsteady large-scale vortex and related shock dynamics have been found for the anti-D shaped rocket sled. However, a quasi-steady flow state exists for the slender-body shaped rocket sled. It indicates that the axisymmetric geometry is more suitable for the effective production of rocket sleds. With the help of power spectral density analysis, we have also determined the characteristic frequencies related to shock-wave/rail-fasteners interaction. Furthermore, a harmonic phenomenon has been revealed, which is intimately related to a shock wave reflection mechanism. © Tech Science Press.