Orbital lymphoma refers to a lymphoma that commonly involves the conjunctiva, lacrimal gland, eyelid and ocular musculature. Primary non1 Hodgkin's lymphoma (NHL) of the orbit is a rare subset, representing only 1% of all NHL and 8-10% of extranodal NHL. We report a case of 24 year old female presented with redness, swelling, an intermittent pain and gradual protrusion of the right eye (RE) since 6 months. Her vision in RE was 6/60 and in Left eye (LE) 6/6. Intraocular pressure (IOP) was 16 mmHg in Both Eye. On examination, RE was proptosed 30mm approximately. Extraocular movement were restricted in all gazes, conjunctiva was chemosed and congested. LE was within normal limits. No lymph nodes were palpable. Ultrasonography of the right orbit showed a mass in the lateral aspect in extraconal space extending to the superior, lateral and retrobulbar region. CT scan of the right orbit showed a mass encasing the extraocular muscles and displacement of the optic nerve. FNAC reports were suggestive of non-Hodgkin's Lymphoma of the right orbit. She was given 6 cycles of RCHOP regime which includes (rituximab, cyclophosphamide, hydroxydaunorubicin, oncovin and prednisolone). Follow-up during each cycle of chemotherapy was done and showed good response initially. Even though rare, primary orbital NHL should be kept in considerat Conclusion- ion in a young female patient with slow growing unilateral Proptosis. After imaging & diagnostic biopsy, patient should be immediately staged & treated. Early diagnosis and treatment improves survival.