Pheochromocytomas/Paragangliomas(PPGLs)are rare neuroendocrine tumors with a high hereditary predisposition.The pseudo-hypoxic PPGLs dominated by SDHx mutations show a higher potential of metastasis.Ap-proximately 10%-17%of PPGLs develop metastasis and patients with metastatic diseases have restricted treatment options and a poor prognosis.Tumor immune microenvironment(TIME)plays a crucial role in the development and progression of tumors as well as predicting patients'prognosis and their response to immune checkpoint inhibitors.Several studies have initially characterized the immune landscape of PPGLs.This review focuses on the infiltration of immune cells,the expression of immune checkpoints in the TIME of PPGLs and their relationships with genetics and metastasis of tumors in order to better understand the mechanisms of tumor immune evasion in PPGLs and pro-vide insights to support novel treatment strategy for metastatic PPGLs.