[Problem] To stably produce dry laver having a desired quality even if pigments or the like flow out of cells or bubbles are generated due to freshness and quality of laver progenitor algae or mince treatment before blending and the like. To provide a dried laver production system capable of According to the present invention, a nori raw material prepared by mixing a nori original algae and water in a mixing device (7) is formed in a paper making device (8) to form a nori dough, and the formed nori dough is dried. In the dried laver production system (1) for producing dried laver by drying with the device (10), measurement is performed by the second sensor (13) from the transmitted light amount of the laver raw material or laver cloth measured by the first sensor (12). The difference light amount obtained by subtracting the transmitted light amount of water contained in the dried seaweed raw material is displayed. Further, the thickness of the dried nori is controlled based on the difference light amount obtained by subtracting the transmitted light amount of the water contained in the nori raw material from the transmitted light amount of the nori raw material or the nori dough. [Selection] Figure 2【課題】海苔原藻の鮮度や品質や調合前のミンチ処理などに起因して細胞から色素等が流出したり泡等が発生しても、所望の品質を有する乾燥海苔を安定して製造することができる乾燥海苔製造システムを提供すること。【解決手段】本発明では、調合装置（７）で海苔原藻と水とを調合した海苔原料を抄製装置（８）で抄製して海苔生地を形成し、形成された海苔生地を乾燥装置（１０）で乾燥して乾燥海苔を製造する乾燥海苔製造システム（１）において、第１のセンサー（１２）で計測した海苔原料又は海苔生地の透過光量から第２のセンサー（１３）で計測した海苔原料に含まれる水の透過光量を差し引いた差分光量を表示することにした。また、海苔原料又は海苔生地の透過光量から海苔原料に含まれる水の透過光量を差し引いた差分光量に基づいて乾燥海苔の厚さを制御することにした。【選択図】図２
