There is provided a hydrogel-forming material, a premix, and a method for forming a hydrogel, which can form a hydrogel through a relatively simple process and under relatively gentle conditions in terms of temperature (at room temperature).A hydrogel-forming material comprising: a disperse phase (A) including a lipid peptide-based gelator consisting of at least one of a compound of Formula (1) or a pharmaceutically usable salt thereof, water, and a fatty acid salt; and a disperse phase (B) that includes a water-soluble acidic polymer:(where R1 is a C9-23 aliphatic group, R2 is a hydrogen atom or a C1-4 alkyl group that optionally has a C1-2 branched chain, R3 is a -(CH2)n-X group, n is a number of 1 to 4, X is an amino group, a guanidino group, a -CONH2 group, a 5-membered ring optionally containing 1 to 3 nitrogen atom(s), a 6-membered ring optionally containing 1 to 3 nitrogen atom(s), or a condensed heterocycle that contains a 5-membered ring and a 6-membered ring optionally containing 1 to 3 nitrogen atom(s)).