Wire-EDMing process has been more accepted for cutting and slicing silicon wafer as it can provide a cut with less crack and chipping due to low effect of mechanical stresses. In order to provide a deep analysis of the process, the wire-EDMing performances and cut surface characteristics of p-type (100) monocrystalline silicon wafer have been experimentally investigated in this study. The results have shown that wide kerf width, high material removal rate, large electrode wear and rough cut surface can be obtained under the condition of high open voltage and rough cutting mode. Some micrographs of cut surface morphology have been also reported and discussed, where many craters and small holes can be apparently seen on the machined surface.