Hydrogels are three-dimensional, hydrophilic networks, comprising polymeric chains linked through physical or chemical bonds. In the area of food, hydrogels have great potential to be used in food packaging systems or as carriers of bioactive components. This paper reviews the nature of hydrogels, their 3D network conformation, their functional properties, and their potential applications in food packaging systems. Regarding their potential food packaging applications, hydrogels can present a conformation which allows their use as part of a packaging system to control the humidity generated by food products with high water content. Moreover, the incorporation of nanoparticles into hydrogels may grant them antimicrobial activity. Finally, although the current research in this field is still limited, the results obtained so far are promising for innovative and potential applications in the food field, which also include their integration into intelligent food packaging systems and their direct incorporation into food matrices as a flavor carrier system.