PURPOSE: To provide mold powder which interrupts contact of copper alloy containing active metal with atmosphere, has inclusion absorption power, improves heat insulating effect of molten metal in lubricitry, and further causes no troubles in aggravation of working environment, nozzle clogging, treatment of used mold powder, etc.

CONSTITUTION: In the mold powder to be used at the time of continuously casting the copper alloy containing the active metal, one or more kinds among carbonate or bicarbonate of potassium, lithium and calcium are incorporated by 0.5-95wt.%, and further in this, one or two kinds among carbonate or bicarbonate of sodium are incorporated by 0.5-95wt.% therein.