Boron carbide composites in Si-B-C System have been widely studied and applied in excellent engineering materials. These materials are usually used at high temperature. Unfortunately, amorphous Si-B-C ceramics have been few reports regarding the properties of Si-B-B4C ceramics. In this study, the preparation of crystallized Si-B-C system compounds using Si, B, and B4C powders was investigated to determine their potentially for applications as high hardness composites. The samples were prepared at 1673 K for 2 hours in Ar atmosphere. The sintered bodies were cut into 5 х 5 х 10 mm blocks and polished with diamond disk for Vickers hardness. The samples were subjected to X-ray diffraction (XRD) analysis for phase evolution using a powder X-ray diffractometer. The fracture surfaces of the specimens were observed using a scanning electron microscope (SEM) included an energy dispersive X-ray fluorescence spectrometer (EDX) system to estimate the microstructures.