Plant for the continuous production of soap in sheets, in particular for the selective production of soap sheets for washing machines and hand-washing soap sheets, characterized in that it comprises: - at least one mixer (44), into which the components are introduced one at a time to prepare a paste with a gelatinous consistency, with which a dimensionally stable continuous band of soap will then be formed (16), - means for introducing said paste with a gelatinous consistency into a casting box (8), configured to release from this a continuous veil of said paste with a gelatinous consistency intended to be deposited on an underlying conveyor belt (12), - a drying oven (10), in which the veil of paste with a gelatinous consistency, transported by said conveyor belt (12), is dried to form said dimensionally stable continuous soap belt (16), - means (98) for separating said dimensionally stable continuous soap belt (16) from said conveyor belt (12) at the exit from said drying oven (10), - a control and management unit for controlling both the activation phases of said mixer (44), after the introduction of each of the components of the dough, and the pause times at the end of predefined activation phases of said mixer (44) based on specific recipes.