Background: Plasma cell leukemia is a rare malignancy with more than 20% plasma cells in peripheral smear. It is very aggressive form of multiple myeloma with fast progression and poor prognosis. Non-secretory plasma cell leukemia is still rarer form in which there is raised number of plasma cells in peripheral blood and on serum protein electrophoresis no “M” band is seen. Case Report: We hereby report non-secretory plasma cell leukemia, presenting with back pain. MRI spine showed lytic lesions, serum and urine protein electrophoresis failed to showed M band, 90% plasma cells were seen on bone marrow aspiration with diffuse infiltration of plasma cells on bone biopsy.  Conclusion: We report here a challenging diagnosis of non-secretory plasma cell leukemia.