Abstract: A rotary hearth furnace for use in the iron and steel industry comprises a furnace (12, 112) with plan in the shape of an annulus, closed at the bottom by a rotary hearth (14, 114), lined at the top with refractory material (15, 115), and a base (28, 128; 30, 130) of the furnace (12, 112). Said hearth (14,114) comprises a plurality of sectors of an annulus (17, 117; 17?, 117?), all the same as one another and connected to form an annulus, complementary to that of the internal plan of the furnace (12, 112), which rotate around the central axis of the annulus, by means of two concentric sets of wheels (26, 126) arranged according to two circumferences, set at equal instances, with supports (25,125), fixed to the base (28) or below the hearth (114), complementary to two circular rails (20, 120), fixed respectively below the hearth (14) or the base (128). According to the invention, both said sets of wheels (26, 126) and said two rails (20, 120) are positioned in such a way as to have an equal load distribution.