Primary ocular lymphoma can be divided into primary intraocular lymphoma (PIOL) and ocular adnexal lymphoma (POAL) based on their location. Primary vitreoretinal lymphoma (PVRL) is the most common form of PIOL. It is an invasive B-cell malignant tumor and is considered to be a subtype of primary central nervous system lymphoma (PCNSL). Because of the non-specificity of ocular symptoms, it often leads to misdiagnosis. Cytopathological/histopathological identification of malignant cells is the gold standard for the diagnosis of PVRL. Other auxiliary examinations, such as optical coherence tomography and fundus autofluorescence, have been used in the diagnosis of PVRL. The measurement of cytokines and the clonality of B cells and the determination of mutant molecules further improve the accuracy of diagnosis. Current treatments for PVRL include local radiotherapy, intravitreal chemotherapy (methotrexate and rituximab), and systemic chemotherapy, depending on whether non-ocular tissues are involved. Orbital lymphoma is the main form of POAL, and the vast majority of orbital lymphoma originate from B cells. Histopathological subtypes and clinical stages of the disease are the best indicators for predicting prognosis and selecting treatment. Radiotherapy is the first choice in the treatment of isolated low-grade lymphoma. For disseminated and highly malignant lymphoma, chemotherapy with or without radiotherapy should be selected.