The investigating results for the impregnating of BeO-ceramics samples obtained out of single-burnt (50 mass %) and high-fired (50 mass %) BeO powder influence on the physical and chemical properties of the ceramics are presented in the article. The ceramics microstructure is studied. It was established that the average microcrystal's size in the samples after impregnation is smaller then that in the samples without impregnation. The difference in sample's microstructure influences their mechanical strength — the ceramic samples with the impregnation in the Na2CO3 solution have bigger strength then the samples without impregnation do.