[problem] provides transfer hydrogel-forming material and hydrogel can be with simpler method and under conditions of milder. [solution] hydrogel-forming material and hydrogel, thus obtained includes the pharmaceutically available salt of general formula compound represented (1) object similar to the above or at least one type containing: lipid peptide gelling agent Water Additive includes a kind of organic acid or organic salt. (in general formula: R1 indicates that aliphatic group has 9 to 23 carbon atoms R2 indicates hydrogen atom or alkyl, has 1 to 4 carbon atom, can have branch to have 1 or 2 carbon atom R3 indicates (CH2)-n-X groups N indicates 1 to 4 number X represents amino, guanidine radicals ,-CONH2 groups or annelated heterocycles, by 5- or 6-membered ring or 5 and 6 member rings, can have 1 to 3 nitrogen atoms. )
