The previous researches on amino acid of aquatic animals mostly focused on single amino acid requirement and its mechanisms. Recently, more studies reported the relationship between amino acids as well as the interactive effects of related amino acids. In the paper, it is reviewed the recent studies on amino acid relationship, the antagonisms and spare-effects of amino acids. The interactive effects of amino acids and the mechanisms are also reviewed from several aspects, such as functional amino acids, sulfur amino acids and branched chain amino acids. In addition, the significance of investigating the interactions between amino acids as well as the future challenges are discussed.