Multiple myeloma (MM) is a clonal plasma cell disorder with the hallmarks of bone marrow plasmacytosis and in most cases, production of an abnormal monoclonal immunoglobulin detectable in serum or urine protein electrophoresis. Assays that detect free light chain (FLC) are important in the diagnosis and monitoring of light chain only multiple myeloma (Bence Jones myeloma) and AL amyloidosis. Serum free light chain (sFLC) measured by scanning densitometry and electrophoresis lacks sensitivity in diagnosis and has a detection limit many times greater than the upper end of the normal range. Our study was done to know whether sFLC and their ratios can be used in diagnosis suspected cases of MM.