This study aims to explore measures to continuously improve shellfish productivity in the West Sea coastal region (Incheon metropolitan city, Gyeonggi-do, Chungcheongnam-do, and Jeollabuk-do), which has a high proportion of aquaculture among domestic shellfish production areas. To analyze changes in shellfish production in the West Sea coastal region over 52 years, we compared changes in tidal flat area and production by fishery and species from 1970 to 2022 using data from the KOrean Statistical Information Service (KOSIS, 2023). As a result of the analysis, West Sea region over the past 10 years (2013-2022) was a total of 50,092 tons (28,997 tons of offshore fisheries, 21,095 tons of shallow-sea aquacultures), aquaculture ratio accounted for 40.4%. Shellfish production by fishery in the West Sea area for 52 years (1970-2022) includes 23 species of offshore fisheries, and the main species targeted for fishing include sunray surf clams, surf clam, oysters, and manila clam. There are 16 species of shallow-sea aquacultures, and the main species targeted for aquaculture include manila clam, oysters, surf clam, and venus clams. Changes in tidal flat area due to reclamation projects had a significant impact on the production of burrowing shellfish. Over the past 31 years (1987-2018), the change in the area of the West Coast tidal flat decreased 590 km2 from 1,935.4 km2 to 1,345.4 km2, showing a decrease rate of 30.5%, a high decrease compares to other regions across the country. In conclusion, it is believed that the way to continuously improve the productivity of shellfish is to protect natural seed and shell growth areas, selecting habitat suitability and suitable sites for each species, managing seed release, and expanding shellfish seed production and intermediate cultivation infrastructure.