A rare case of extramedullary plasmacytoma (EMP) arising from the lacrimal gland of a 33-year-old woman is presented. The left lacrimal gland tumor was suspected, and tumorectomy was performed. Histopathological examination with immunostaining revealed it to be positive for IgG and chains, demonstrating monoclonality. However, no abnormality was observed on serum protein electrophoresis, immunofixation, or skeletal survey and bone marrow aspiration, and the tumor was diagnosed as EMP. Postoperative radiation was given to the left orbit by a linear at a dose of 40 Gy. One year and 10 months have passed since the operation, and the patients general condition is good, without local recurrence of tumor, lymph node metastasis, or remote metastasis. The EMP should be considered in the differential diagnosis of lacrimal gland tumor.