Feed Additives in Aquafeeds Aquaculture production was realized as 212.000 tons in Turkey and approximately 66 million tons in the world in 2012 respectively. In aquaculture production, the main objective is to obtain maximum yield with minimum cost. In recent years, feed additives are widely used in order to increase fish production. While additives added to fish diets increase digestibility, but they reduce anti-nutritional effects of the fish diets. In addition, the feed additives play roles for fish gaining resistance against diseases. Probiotics to be used as feed additives should not be in pathogenic nature and they should not produce toxic subs- tances. Moreover, they should maintain viability during their storage and their high nutritional interaction with fish feed is more desirable. Some studies demonstrated that the use of enzymes and plant extracts in diets increased live fish weight and voluntary feed intake. In this study reviewed the specific literatu- re investigating probiotics, enzymes and plant feed additives in fish diets.