To provide a powdery quick-setting admixture for refractory, which is mixed with castable refractory and yields sufficient strength at an early age with its addition of reduced amount, sprayable material containing it and spraying method using it to enable reliable and high quality spraying.

The quick-setting admixture contains a crystalline phase comprising 12CaO.7Al2O3 of 40-100%, 3CaO.Al2O3 of 0-30%, and CaO.Al2O3 of 0-30%, optionally with a set.hardening accelerator, and has Blaine fineness of 3,000-6,000 cm2/g. The sprayable material contains the quick-setting admixture and castable refractory containing aluminous cement and refractory aggregate. The castable refractory conveyed by pumping and the quick-setting admixture conveyed by pressurized air are mixed at a spraying nozzle and sprayed.