The invention discloses a horizontal annealing furnace heating section structure. The horizontal annealing furnace heating section structure comprises a furnace body, wherein one side of the furnace body is connected with a preheating section, and the other side of the furnace body is connected with a connection section; a plurality of groups of furnace rollers which are identical in height are arranged in the furnace body, and a steel band is supported by the furnace rollers; the upper side and the lower side of each furnace roller are respectively provided with a nozzle group consisting of a plurality of nozzles, each nozzle comprises a spraying pipe which is horizontally arranged, a spraying opening is formed in each spraying pipe, and the spraying pipes of each group of nozzles are parallel to one another; the nozzle groups at two sides of the furnace rollers are arranged at intervals; and each upper nozzle group and each lower nozzle group form a combustion area. The horizontal annealing furnace heating section structure has advantages that since the nozzle groups are arranged at intervals, during the heating process of a metal, crystal grains generated when the internal metallic tissue is changed are relatively uniform, so that the mechanical performance of strip steel can be improved, and the surface quality of the strip steel is also improved; and the heating section is designed in a sectional manner, so that the steel strip can be uniformly heated, the temperature of a strip steel plate can be adjusted by controlling the production speed and the temperature inside the furnace, the continuous full-load production of a unit is realized, and the production efficiency is improved.