The invention provides a heating furnace without a tie rod. The heating furnace comprises furnace walls which are arranged on two sides oppositely, in parallel and respectively, and a plurality of heat exchange modules which are arranged between the furnace walls on the two sides, wherein the plurality of heat exchange modules are arranged in the lengthwise direction of the furnace walls; each heat exchange module comprises a tube plate and furnace tubes; a plurality of through holes are formed in each tube plate; the furnace tubes run through the different through holes; and mounting parts are arranged on two sides of each tube plate respectively. The heating furnace also comprises bolt assemblies, wherein the mounting parts are fixedly connected with the furnace walls on the corresponding sides through the bolt assemblies, so that in the mounted state, the tube plates and the furnace walls are mutually positioned and supported; and therefore the traditional tie rod can be eliminated,the furnace walls cannot tip over, the mounting is convenient and the manufacturing cost is reduced. Elastic heat-insulating parts are arranged between the mounting parts and the furnace walls; in the working state, thermal expansion occurs to the tube plates to squeeze the elastic heat-insulating parts, thereby causing the elastic deformation of the elastic heat-insulating parts to provide a space for the expansion of the tube plates; and thus the requirement for the thermal expansion of the tube plates is met, and the working requirements of the furnace walls cannot be broken.