The purpose of this study was to determine the contents of water-soluble vitamins B1 (thiamine), B2 (riboflavin), B3 (niacin) and B12 (cyanocobalamin) in seafood-based dishes by using the high-performance liquid chromatography with the ultra violet and fluorescence detector. The vitamin B1, B2, B3 and B12 contents were analyzed in 29 seafood-based dishes. The method validation was performed on the method to determine the linearity, accuracy, limits of quantification, limits of detection and precision for vitamin B1, B2, B3 and B12. An excellent linearity range (R2=0.999~1.000) in the calibration curve for the water-soluble vitamins was observed. All analytical methods for the water-soluble vitamins showed the acceptable accuracy (89.4~119.7% recovery) and the precision (0.6~4.8% repeatability and 1.0~4.2% reproducibility). The highest content of vitamin B1 was 2.646 mg/100 g in the kkongchi-jorim, and the highest contents of vitamin B2, B3 and B12 were 0.370 mg/100 g, 10.971 mg/100 g, and 17.193 μg/100 g, respectively, in the kkongchi-gui. Our results provide reliable data on the contents of the water-soluble vitamins of seafood-based dishes in Korea.