PURPOSE: To obtain a refractory coating compsn. having more excellent fire resistance than conventional compsns.

CONSTITUTION: This refractory coating compsn. is obtd. by mixing a foamable mineral powder material which starts foaming at ≤400°C, 100 to 500 pts.wt. of inorg. compd. powder material which emits incombustible gas by ≥10% of its weight at ≤800°C based on 100 pts.wt. of the foamable mineral powder material, and 2 to 200 pts.wt. binder which gives shape holding property to these powder material and does not inhibit foaming based on the total 100 pts.wt.of the foamable mineral powder and the inorg. compd. powder. The foamable mineral powder is preferably unburned vermiculite.