Abstract: An apparatus for continuous heat treatment of wire rod comprises a tank containing a water bath maintained at a temperature of at least 75.degree. C., at least one inlet conveyor having an emergent part and a immersed part which is immersed in the water bath, and at least one outfit conveyor having an immersed part immersed in the water bath and an emergent part, the inlet conveyor having a plurality of steps inside the tank which are lower than the maximum upper level of the water bath, and at least one of the steps of the inlet conveyor having a downward inclination not exceeding 3.degree. to horizontal in the direction of conveyor movement, successive steps of the inlet conveyor being interconnected by at least one conveyor section inclined downwardly in the direction of conveyor movement at an angle not exceeding 10.degree. to horizontal. The level of the water bath is varied so that one or more of the steps of the inlet conveyor can be immersed selectively and optionally.