This study evaluated economic feasibility and provided rationale for the development of the Korean Operational Oceanographic System (KOOS). KOOS is supposed to be established for the preservation and management of marine environments, and for the safety of ocean activities. Economic issues associated with operational oceanographic systems are discussed. During the operational period of KOOS associated with conservative small-input scenarios, and according to the macroeconomic inputoutput analysis, the system was estimated to generate 8.3 times its actual proposed economic investment (about KRW 327.7 billion). Other rationales that cannot be easily quantified were also discussed.