Abstract: Recently, metal nitrides (MNs) have received renewed attention due to their potential as catalytic materials in energy transformations, with water spitting and CO2 reduction being the most studied reactions Reactions considered in this review are limited to photocatalysis Moreover, the morphology, size, defects and nanostructured construction of MNs are demonstrated to be critical factors in their catalytic efficiency, emphasizing the importance of their synthetic method Mono, binary, ternary and doped nanostructured MN materials have been synthesized and evaluated as photocatalysts The latest research is focused on the development of new synthetic methods, cocatalysts, and constructure design, aiming to achieve improved activity, selectivity, and stability This review provides a broad overview of the development of photocatalysts for the generation of H2 and CO2 reduction reaction, summarizing the current state of work focusing on the recent progress in light-induced overall water splitting and CO2 reduction on metal nitride photocatalysts