The curing process and quasiceramic properties of vinylcontaining polysilazane ceramic precursor PSN1 were studied. TGA and DMA were employed to investigate the thermal properties. The data show the decomposition temperature and the residue weight of the quasi-ceramic matrix with the increase of quasi-ceramic temperature,580 and 87% are achieved under N2 atmosphere while above 550 and 95% are achieved under air atmosphere respectively. No obvious Tgof the 420 guasi-ceramic is observed below 400. Network vector analyzers data show the dielectric constant is below 3 and just changed slightly with the temperature and frequency. Water uptake measurement shows the quasi-ceramic matrix has low water uptake properties, with the minimum of 0.03%. All the data show the quasi-ceramic PSN1 matrix is potential to be used in wave-penetrating composites.