To provide an operation method of hearth rolls in an annealing furnace by which a creep deformation causing uneven wear, and also, defective surface quality developed in a product with the deformed hearth roll are restrained when a conveyance of metal strips is stopped in the annealing furnace.

The annealing furnace 5 is provided with plural hearth rolls 8 for carrying and supporting the metal strips S. During stoppage of the carrying of the metal strips S, the divisions of a supporting state for supporting the metal strips S in periodic time interval to each of plural hearth rolls 8 and a standby state for separation the metal strips S from the hearth roll, are changed over, and also, the hearth roll 82 in the standby state is rotated so as not to develop the deflection.