Abstract: Hypoxia, which is common in a variety of solid tumors, can easily lead to the failure of anti-tumor treatments (such as chemotherapy, radiotherapy, light therapy, sonodynamic therapy, etc.), and may eventually lead to the deterioration and metastasis of tumor. In recent years, many new nanotechnologies have emerged and have been used to reverse tumor hypoxia, thereby reducing the occurrence of treatment resistance. The existing nano-oxygen carriers mainly directly include delivering oxygen to the tumor and generating oxygen in situ. This review summarizes the research progress of nanotechnology in tumor oxygen supply in the past five years from the design of nano-oxygen carrier and its application in tumor diagnosis and treatment, in order to provide references for related research.