Metabolic reprogramming is one of the important hallmark of cancer. To meet the anabolic demands of the proliferative potential of tumor cells malignant cells tend to rewire their metabolic pathways. Radiation therapy is an important means for the treatment of malignant tumors. Compared with normal cells tumor cells have a large amount of metabolic heterogeneity from the development of precancerous lesions to local invasion metastasis or treatment resistance the metabolic phenotype and metabolic dependence may change. Radiation resistance has always been the main reason for limiting the efficacy of radiation therapy and is also a difficult and hot spot in the research of anti - tumor therapy. Tumor radiotherapy resistance is closely related to metabolic reprogramming. The special aerobic glycolysis mode of tumor cells creates a high lactic acid microenvironment which is not conducive to the role of radiation The accumulation of antioxidant molecules during metabolism can protect tumor cells from radiation damage of free radicals Under irradiation tumor cells need more energy supply and the synthesis of biological macromolecules to promote DNA damage and repair and flexible metabolic mode conversion provides conditions for it. The difference of metabolic patterns between normal tissues and malignant cells provides an opportunity for targeted metabolic therapy. This article reviews the relationship between the main metabolic pathways of tumor and radiotherapy hoping to reverse the radiation resistance and improve the sensitivity of tumor radiotherapy through targeted metabolism.