Solar‐driven photocatalysis with graphitic carbon nitride (g‐C3N4) is considered to be the most promising approach for the generation of H2 from water, the degradation of organic pollutants, and the reduction of CO2. However, bulk g‐C3N4 exhibits several drawbacks, such as a low specific surface area, high defect density, and fast charge recombination, which result in low photocatalytic performance. The construction of 3D porous hydrogels for g‐C3N4 through nanostructural engineering is a rapid, feasible, and cost‐effective technique to improve the adsorption capability, stability, and separability of the hydrogel composite; to increase the number of active sites; and to create an internal conductive path for facile charge transfer and high photocatalytic activity. This minireview summarizes recent progress in photocatalytic water splitting and dye degradation by using g‐C3N4‐based hydrogels, with respect to state‐of‐the‐art methods for synthesis, preparation, modification, and multicomponent coupling. Furthermore, comprehensive outlooks, future challenges, and concluding remarks regarding the use of g‐C3N4‐based hydrogels as highly efficient photocatalysts are presented. Gelling to split: Recent developments in graphitic carbon nitride (g‐C3N4)‐based hydrogels, with regard to synthesis, preparation, and multicomponent coupling, and their photocatalytic reactions, including water splitting, wastewater purification, and CO2 reduction, are reviewed. Particular focus is given to g‐C3N4‐based hydrogels as photocatalysts.