The invention relates to a method for heat treating elongated products (L), in particular metal elongated products (L) such as wires, sheets, or the like made of steel, wherein the elongated product (L) is conducted through a furnace (2) having at least one heating apparatus (3) for heating an atmosphere (4) and through an inlet (5) and an outlet (6), wherein the elongated product (L) can be inserted into the furnace (2) through the inlet (5) and can be discharged from the furnace through the outlet (6) and wherein the elongated product (L) conducted through the furnace (2) is heated by means of the heated atmosphere (4). According to the invention, in order to achieve a heat treatment of the elongated product (L) effectively in an economical manner, the atmosphere (4) is conducted in a circuit (K1) in the furnace (2), wherein the atmosphere is laterally incident on the elongated product (L) conducted through the furnace. The invention further relates to a device (1) for heat treating elongated products (L).