The present invention relates to a preparation method of fish sauce seasoning, the method comprising: (a) decolorizing and deodorizing a liquid fish sauce; (b) concentrating the fish sauce from the step (a) and crystallizing salts contained in the fish sauce; (c) separating the fish sauce concentrate (b) and the crystallized salts; and (d) repeating the (b) and (c) steps at least once, and to a fish sauce seasoning prepared by the method. The fish sauce seasoning of the present invention has a high total nitrogen content and is a natural seasoning material as chemical additives are neither contained in raw materials of the seasoning nor added during a processing thereof, and the seasoning's nicely salty and palatability makes it useful as a substitute material for MMG and nucleic acid that are classified as synthetic additives.