Total fluorine concentrations in some fish species and seafood such as mussels, squid (calamary), and shrimp were determined using the molecular absorption of calcium monofluoride (CaF) generated in a graphite furnace using a high-resolution continuum source atomic absorption spectrometer and direct solid sampling. The fish fillets and seafood were dried at 110 degrees C, minced finely, put on the platform using masses less than 1.2mg, and introduced to the graphite furnace with 20 mu g of calcium by a solid sampling accessory. The effects of CaF wavelength, graphite furnace program, amount of sample introduced to the furnace, the use of modifier on the determination of fluorine were investigated and optimized. The absolute limit of detection and characteristic mass of the method were 0.28 and 0.14ng of fluorine, respectively. By applying the optimized parameters, the concentrations of fluorine in various fish species and seafood were determined.