Organoids are the three-dimensional culture of adult stem cells or pluripotent stem cells in vitro to form tissue analogs with specific structures,which have highly similar tissue properties and physiological functions to the corresponding organs.The emergence of organoid technology has laid an important foundation for research in organ development,disease modeling and drug discovery.Tumor organoid,as an important branch of organoids,is a transition between cell lines and animal models,which can well retain the histological and mutational characteristics of tumors in patients and play an essential role in building tumor organoid sample libraries,reconstructing tumor microenvironment,studying the tumor development mechanism as well as formulating personalized treatment plans and drug screening.Tumor organoids help clinicians to realize precise treatment for patients.However,some factors still limit the further development of tumor organoids,such as the lack of microenvironmental components,vascular structure,high culture cost and technical difficulties.In this review,we summarize the applications and challenges of organoid technology in basic tumor research and clinical translation and look forward to the future development of tumor organoids.