The authors report four cases of POEMS Syndrome with renal involvement. Two had renal failure and mild proteinuria. The two others had hyporeninemic hypoaldosteronism with type IV renal tubular acidosis in the first and hyperkalemia alone in the second. In the two cases, renal biopsy showed mesangial proliferation. Evolution was favourable when the plasma cell proliferation could be checked. In POEMS pathophysiology of renal involvement remains unknown. Soluble factor(s) produced by plasma cells may be responsible for most signs and symptoms perhaps as a result of increased vascular permeability.