PROBLEM TO BE SOLVED: To provide a method of keeping the freshness of a fresh seafood product which can transport the fresh seafood product without deteriorating its freshness and taste even when the fresh seafood product is freezed.SOLUTION: A method of keeping the freshness of a fresh seafood product includes the steps of manufacturing ice slurry by mixing ice made by freezing saline water having the salinity concentration of 13.6-23.1% and saline water having the salinity concentration of 13.6-23.1%, and instantaneously freezing the fresh seafood product after immersing the fresh seafood product in the ice slurry.SELECTED DRAWING: Figure 2【課題】生鮮海産物を凍結させても鮮度、味覚が落ちることがなく、遠隔地まで長時間輸送することが可能な生鮮海産物の鮮度保持方法を提供する。【解決手段】本発明の生鮮海産物の鮮度保持方法は、塩分濃度が13.6~23.1%である塩水を凍結させた氷と、塩分濃度が13.6~23.1%である塩水とを混合して氷スラリーを製造する工程と、氷スラリーに生鮮海産物を浸漬し、該生鮮海産物を瞬間凍結させる工程と、備えている。【選択図】図2