A drying system includes: drying furnaces connected in series; an air supply system including an air supply pipe, the air supply system being configured to supply dry air into the furnaces, and an air exhaust system including an air exhaust pipe, the air exhaust system being configured to exhaust wet air in the furnaces, wherein the air supply system and the air exhaust system are being alternately connected between the drying furnaces; a first flow rate regulation valve provided to the air supply system; and a second flow rate regulation valve provided to the air exhaust system.