X‐rays, a form of ionizing radiation with high energy and significant penetration capability, are commonly used in clinical tumor treatment through radiotherapy. Despite their widespread use, optimizing X‐ray efficacy remains a critical challenge due to issues such as radiation resistance and damage to surrounding health tissues. Recent advancements in nanotechnology have introduced new opportunities and challenges in cancer diagnosis and treatment. This review summarizes the latest progress in nanomaterials for X‐ray‐triggered cancer therapy, highlighting their various advantages such as targeted delivery, reduced side effects, and enhanced therapeutic efficacy. We examine how nanomaterials, including metals, metal oxides, metal sulfides, metal fluorides, rare earth oxides, cluster compounds, metal‐organic frameworks, and nanohybrids, enhance the effectiveness of X‐ray‐triggered treatments. Furthermore, we address the current challenges and future prospects of efficient X‐ray‐triggered cancer therapy, aiming to provide a comprehensive overview for researchers and clinicians in the field.