A gelator made of an aliphatic oxyglycyl polyol that is capable of forming a gel by a small amount of addition in a pH range from acidic to alkaline regions, and a gel having high environmental compatibility, biocompatibility and biodegradability. A gelator including an aliphatic oxyglycyl polyol of Formula (1) wherein R is a C18-20 saturated aliphatic group or a C18-20 unsaturated aliphatic group having one double bond) or a pharmaceutically usable salt thereof a self-assembly formed by self-assembling of the gelator and a gel comprising the gelator or the self-assembly, and water, an alcohol, an aqueous solution, an alcohol solution, a hydrophilic organic solution, or a hydrophobic organic solution.
