A ballistic projectile launching device was used to study the penetration behaviors of tungsten alloy spherical fragments of various diameters into carbon fiber composite target plates of different thicknesses. Based on the ballistic test results, we obtained the relationship between ultimate penetration velocity, target plate thickness, and fragment diameter as well as the relationship between the fragment penetration energy and fragment incident velocity. Using dimensional analysis, we obtained a formula relating the incident fragment velocity and the fragment penetration energy, which showed good agreement with the experimental values. We also analyzed the main fracture mode and the energy absorption mechanism of the carbon composite target plate under high-velocity impacts of tungsten alloy spheres and investigated the experimental damage modes of the target plate at different fragment velocities during the ballistic impact.