We report a rare case of primary renal allograft dysfunction due to myeloma cast nephropathy in a patient with no overt clinical features of multiple myeloma preceding his transplantation. A 45-year-old man on hemodialysis for six months for end-stage kidney disease due to presumed chronic glomerulonephritis developed immediate graft dysfunction post-transplantation. The graft biopsy was diagnostic of myeloma cast nephropathy. Other criteria for lambda light chain multiple myeloma were fulfilled with immunofixation electrophoresis and bone marrow biopsy. He was treated with plasmapheresis, bortezomib and high-dose dexamethasone. However, the patient succumbed to septicemia on the 37 th post-operative day. This is probably the first report of primary renal allograft dysfunction due to myeloma cast nephropathy diagnosed within the first week post-transplanation in a patient with unrecognized multiple myeloma.