The metal elements, such as Fe, Mn, Co, Ni, Ni-Mn, Co-Mn and Fe-Mn, were mixed and milled with pre-cross-linked polysilazane Ceraset® and subsequent pyrolysis. The metals act as active fillers to increase the density of composite. The phases and microstructures of metal/ceramic composites were studied using XRD, SEM and EDS, and the magnetic property was measured with Magnetic Property Measurement System at –196oC. The results show that there are two main domains in composites, one is metal-rich domain and another is metal-poor domain. The density of composite is larger than that of polymer-derived SiCN ceramic, but the hardness varies little. The compound generated by the reaction between metal and matrix has great effect on the magnetic properties of composites, which are filled with different metals.