Monoglycerides (MGs) and diglycerides (DGs) are polar lipid molecules consisting of one or two fatty acids esterified to a glycerol molecule. These molecules have the peculiar ability to form supramolecular structures leading to a three-dimensional network able to retain huge amounts of solvents. Thanks to their amphiphilic nature, MGs and DGs can be used to entrap water, oil, or both the solvents, resulting in a plethora of structured systems such as gels, foams, and emulsions, showing the functionalities of conventional fats. By controlling the formulation and processing conditions, a wide range of compositional and rheological properties can be covered, allowing for these systems to be used as fat mimetics in different food products. In this chapter, the fat mimetics that can be prepared based on the structuring ability of MGs and DGs are discussed. After an initial description of the main characteristics of these molecules, the different MG-and DG-based structures formed in different environments (i.e., hydrogels, oleogels, oleofoams, gelled emulsions) are described in depth, considering their hierarchical structural organization as well as the main factors affecting their structure and properties. Finally, food applications of the relevant fat mimetics are reviewed.