Abstract: The resistant of hypoxia tumor cell to radiotherapy and chemotherapy is one of the reasons that lead to therapy failure. To detect the distribution difference of hypoxia and glycometabolism in vivo is helpful to revise radiotherapy plan in order to improve the therapeutic effect, or to evaluate the prognosis shortly after radiotherapy and chemotherapy. TTie deposition of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) mainly depends on blood flow with weak relation to uptake rate, and only reflects the membrane flux of glucose without distinguishing aerobic metabolism, enhanced cell proliferation and hypoxia tissue. Clinical experience indicated that ¹⁸F-FDG could integratedly reflect the malignant degree of tumor for the more difference between the distribution of hypoxia and glycometabolism, the more invasion of the tumor. The distribution of ¹⁸F-FDG and ¹⁸F-fluoromisonidazole were similar in general, but can not exclude minor deference. Current studies can not deny ¹⁸F-FDG as a hypoxia agent with a limited value and specificity.