This invention provides monoglycerides containing a conjugated fatty acid, and a process for producing the above described conjugated fatty acid containing monoglycerides in which all kinds of lipases can be used as catalysts.This invention relate to monoglycerides containing a conjugated fatty acid (preferably in an amount of 50% or more of fatty acids).This invention also relates to a process for producing the conjugated fatty acid containing monoglycerides, in which the conjugated fatty acid containing a free fatty acid and glycerol are subjected to the reaction of esterification, or of esterification and glycerolysis in the presence of lipase as a catalyst.