Pressed fish cake from mackerel (Trachurus Murphyi) was dried under various conditions (mixing intensity, size of particles, wall and air temperature) in an impingement drier. Drying was significantly influenced by air temperature and particle diameter and occurred at constant rates. An extended penetration model is used to describe the drying process. Calculations are compared to experimental drying rate curves. The susceptibility of n - 3 fatty acids of pressed fish cake to oxidation during drying under different conditions was determined by GC analyses of the methylesters of fatty acids. Results indicate that the increase in water content of pressed fish cake inhibits oxidative reactions.