A heat-insulating protective member for skid posts contains a needled blanket of inorganic fibers. At least some of the needled blanket has, disposed therein, an impregnation part where an oxide-precursor-containing liquid is adherent in an undried state. The impregnation part has a water content of 50-400 parts by mass per 100 parts by mass of the inorganic fibers of the impregnation part. The water content of the heat-insulating protective member is 50-400 parts by mass per 100 parts by mass of the inorganic fibers of the heat-insulating protective member. The oxide-precursor-containing liquid contains ingredients that, upon burning, yield a composition containing Al2O3 and CaO. The oxide-precursor-containing liquid is adherent in an amount of 2-50 parts by mass in terms of oxide amount per 100 parts by mass of the inorganic fibers of the impregnation part. A molar ratio of Al/Ca, in the whole impregnation part is 10-330.