The invention discloses a method and a device, which are used for generating superheated steam from high-salt boiler feed water through stage evaporation, and belongs to the technical field of boiler equipment. According to the method, a boiler drum is divided into a net section and a salt section; the lower part of a salt-section cyclone is connected with the salt section to achieve discharging; the bottom end of the salt-section cyclone is connected with a salt-section down pipe, the salt-section down pipe is connected with a salt-section distribution header, the other end of a salt-section riser pipe is connected with the middle of the salt-section cyclone, a cavity body in the upper part of the salt-section cyclone is connected with a corrugated plate, the top of the salt-section cyclone is connected with a salt-section steam outlet, and the salt-section steam outlet is connected with a pipeline at one end of a super heater; the net-section distribution header is connected with a net-section riser pipe; a salt-section communication pipe is used for communicating a net-section steam drum with the salt-section cyclone. The method has the benefits that the requirement on the salt content of boiler water in a heavy oil thermal recovery boiler is greatly lowered on the premise of guaranteeing the steam quality, moderately treated heavy oil recovery water can be reused, heavy oil development water can be recycled, the clear water consumption and the sewage discharge are reduced, the environment is protected, and the heavy oil thermal recovery cost is reduced.