Powder compacts with some different compositions of Nb-Si-Al-Cr system were prepared by spark plasma sintering (SPS), and oxidation behavior of each compact was examined by a thermobalance. In addition, some Nb substrates were coated with Cr-doped Nb(Si,Al)(2) by SPS and low pressure plasma spraying (LPPS), and then their microstructure was observed. Cr-doped Nb(Si,Al)(2) Matrix compacts with a composition of Nb-56Si-11Al-3Cr (at%) showed extremely good oxidation resistance in the temperature range of 773K to 1673K. The Cr-doped Nb(Si,Al)(2) layer adhesively stuck to Nb substrate when thin Al foil was inserted between Cr-doped Nb(Si,Al)(2) powder and the substrate before the SPS. Moreover, Cr-doped Nb(Si,Al)(2) layer adhesively stuck to Nb substrate when the substrate was SPSed under conditions of pseudo hot isostatic pressing after the LPPS.