Abstract: Demanded widely in numerical calculations, the high-pressure state equations of limestone were studied for civil engineering, such as tunnel blasting, mineral mining, weapon damage effects, and engineering protection with the limestone distributed widely in the Earth's crust. To investigate the high-speed impact compression characteristics of limestone, the high-speed impact experiments were arranged to carried out 21 high-speed impact tests for three types of limestone, taking a 20 mm-diameter two-stage light gas gun as the main equipment. Based on velocity measurement probes, high-speed cameras and high-sensitivity pressure sensor equipment, the flyer plate velocity and shock wave duration were measured, showing the range of flyer plate velocity from 1.02 km/s to 3.91 km/s. Combining with the known material parameters of the flyer plate and limestone specimens, the calculating pressure generated with high-speed impact was presented, ranging from a minimum of 5.64 GPa to a maximum of 30.22 GPa. The linear relationship between the shock wave velocity D and particle velocity u in limestone was analyzed with the least squares method, yielding D = 2.887 + 0.798u for Type A limestone, D = 2.872 + 0.892u for Type B limestone, and D = 2.575 + 1.086u for Type C limestone. A nonlinear fit of the relationship between shock pressure p and volumetric strain μ in limestone was performed based on a two-parameter cubic polynomial, resulting in p = 145.28μ³ + 24.44μ for Type A limestone, p = 169.18μ³ + 25.45μ for Type B limestone, and p = 206.57μ³ + 21.10μ for Type C limestone. The analysis results of the limestone mineral composition show that the more of the mineral content with higher density and hardness, the faster of the growth rates both shock wave velocity and shock pressure in limestone resulted from increased flyer plate impact velocity. The research results provide valuable data support for the parameter calibration of constitutive model state equation of limestone.