In order to verify the validity of ground-probing radar in search for the fractured zone of bedrock and identify characteristics of its GPR profile, the authors built a fairly good fault zone model by assuming the dielectric constant of the fractured zone which is distributed randomly in a certain spatial range. Using finite-difference time-domain (FDTD) simulation method, the authors obtained the two-dimensional GPR forward profile of the fracture broken belt that can better reveal its features on the GPR profiles. Through simulating different fractured zone models with different crushing degrees or different bedrock dielectric constants, the authors are fully acquainted with their characteristics on GPR profiles. A practical example shows that characteristics of the fractured zone revealed in forward simulation also exist in the practical GPR detection profile. It can thus be concluded that the forward simulation is a practical and reliable means in providing supports for the interpretation of practical GPR profiles.