Environmental pollution and energy shortage pose major challenges to sustainable development. Photocatalytic technology using solar energy for pollutant degradation and resource conversion is a promising solution. However, conventional photocatalysts and reactors have limitations such as narrow light absorption, fast charge recombination, difficulty in recovery and continuous operation. The characteristics of surface reactions in photocatalytic technology also put forward higher requirements for light field design. 3D printing (Additive manufacturing) provides an innovative strategy to solve these problems. It enables the controllable design of photocatalyst microstructures in terms of pore size, morphology and surface characteristics through high-precision and customizable manufacturing methods, thus significantly improving the specific surface area, enhancing the light capture ability and carrier separation efficiency. At the same time, 3D printing technology can also manufacture photocatalytic reactors with complex flow channel structures, multi-scale mass transfer interfaces and integrated functional units, which can effectively optimize the distribution and transmission of reactants and light, realize the collaborative enhancement of reaction-mass transfer-illumination, and support the system integration of multifunctional modules. This review systematically summarizes the technical progress, core challenges and application potential of this cross-field, and provides reference for the subsequent research on 3D printing innovation of photocatalytic materials and devices.