The invention belongs to the technical field of hot zinc plating equipment and particularly relates to a hot zinc plating furnace. A furnace body is included, and internally provided feeding devices,a conveying belt and a liquid level sensor; the feeding devices are symmetrically installed on the side wall of the middle portion of the furnace body, and each comprises a shell, a number one spring,a suction cup, an electric push rod and a controller; a pressing plate is connected to the bottom of each electric push rod; the liquid level sensor is used for transmitting the hot zinc plating capacity in the furnace body to the feeding devices in a signal type; the feeding devices are used for conveying zinc blocks into hot zinc plating liquid due to cooperation of the number one springs, thesuction cups and the pressing plates., and the purpose of performing automatic material adding on the furnace body is achieved; and casualties caused by manual feeding and device damage are reduced, outside impurities doped into the furnace body during manual feeding can also be reduced, generation of lots of zinc slag in the furnace body is reduced, and therefore the production quality of the hotzinc plating furnace is improved.