A fixed-bed multi-tubular reactor for producing an alkenyl acetate, comprising: a supply line of a raw material gas and a mist of an aqueous solution of an alkali metal acetate, a plurality of reaction tubes to which the raw material gas and the mist of an aqueous solution of an alkali metal acetate are supplied through the supply line from an upper part of the fixed-bed multi-tubular reactor and each of which has an inlet opening, wherein the upper ends of the reaction tubes are fixed by an upper fixing plate representing an upper plane and the lower ends of the reaction tubes are fixed by a lower fixing plate, the plurality of reaction tubes being straight tubes and being installed in a vertical direction, a thermometer protection tube inserted into at least one of the plurality of reaction tubes from the upper part of the fixed-bed multi-tubular reactor, a thermometer inserted into the thermometer protection tube, and a shield disposed inside the fixed-bed multi-tubular reactor above the reaction tube into which the thermometer protection tube is inserted and attached to the thermometer protection tube, wherein an effective projection region of the shield entirely covers the inlet opening of the reaction tube into which the thermometer protection tube is inserted, wherein the effective projection region of the shield is an area on the upper plane obtained by projecting, in the vertical direction to the upper plane of the reaction tube into which the thermometer protection tube is inserted, an area surrounded by line segments connecting points of the shield at which liquid droplets are separated from the shield and drop, when the mist of an aqueous solution of an alkali metal acetate contacts the shield and flows down as the liquid droplets. a supply line of a raw material gas and a mist of an aqueous solution of an alkali metal acetate, a plurality of reaction tubes to which the raw material gas and the mist of an aqueous solution of an alkali metal acetate are supplied through the supply line from an upper part of the fixed-bed multi-tubular reactor and each of which has an inlet opening, wherein the upper ends of the reaction tubes are fixed by an upper fixing plate representing an upper plane and the lower ends of the reaction tubes are fixed by a lower fixing plate, the plurality of reaction tubes being straight tubes and being installed in a vertical direction, a thermometer protection tube inserted into at least one of the plurality of reaction tubes from the upper part of the fixed-bed multi-tubular reactor, a thermometer inserted into the thermometer protection tube, and a shield disposed inside the fixed-bed multi-tubular reactor above the reaction tube into which the thermometer protection tube is inserted and attached to the thermometer protection tube, wherein an effective projection region of the shield entirely covers the inlet opening of the reaction tube into which the thermometer protection tube is inserted, wherein the effective projection region of the shield is an area on the upper plane obtained by projecting, in the vertical direction to the upper plane of the reaction tube into which the thermometer protection tube is inserted, an area surrounded by line segments connecting points of the shield at which liquid droplets are separated from the shield and drop, when the mist of an aqueous solution of an alkali metal acetate contacts the shield and flows down as the liquid droplets.