Cancer is a major threat to human life and health globally and is second only to cardiovascular disease in terms of morbidity and mortality. Cancer remains a focus of attention of health services worldwide. Good animal models can not only be used to study the occurrence, development, and biological mechanisms of cancer but also to screen anticancer drugs and gene therapies. In recent years, patient-derived xenograft (PDX) models have become a research hotspot due to their ability to preserve the microenvironment and histological characteristics of primary tumors. This review summarizes the method of PDX animal modeling and its application in oncology medicine, as well as its limitations, providing an important reference for the application of PDX models in the field of tumor therapy.