Polycarbosilane (PCS) was introduced into preforms to prepare W-ZrC cermets by reactive melt infiltration (RMI). Properties and microstructure of the preforms and cermets were analyzed with XRD, SEM and EDS. The preforms had an open porosity of 42.0 %, and the WC particles were cemented by the pyrolysate of PCS. W-ZrC cermets were prepared by heating Zr2Cu covered preforms to 1300 °C for 3 h. XRD revealed that the resulting cermets were made up of W, ZrC and W2C. The cermets had an open porosity of 3.5 %, a flexural strength of 354.0 MPa, a flexural modulus of 192.5 GPa and a flexural toughness of 5.72 MPa·m1/2 .