This study was carried out in the Deparment of Internal Medicine, University of Ankara Medical School, Turkey.The permanganate reaction was applied to a series of amyloid samples. Tissue were obtained from 22 patients in whom the diagnosis of amyloid had been made at renal biopsy. In’clinical classification, of these 22 patients six were Irimary amyloidosis, 8 secondary froms, 3 familial Meditterranean fever (FMF) and 3-were unclassified. Six patients with primary amyloidosis had uniformly permanganate resistant deposits. Of the 8 patients clinically judged to have secondary amyloidosis, 5 exhi- bited permanganate sensitivity in all amyloid deposits studied. However, in two pa- tients so categorized the deposits were resistant to potassium permanganate and in another one patient the reaction was mixed. Of the 3 patients associated with FMF, 2 exhibited permanganate sensitivity and in another one patient the reactian was mixed. Of the 5 patients unclassificd clinically, 3 exhibited permanganate sensivity in all amyloid deposits studied, in one patient deposits were resistant to potassium permanganate and in another one patient the raction was mixed. In final classification bdsed n the potassium permanganate reaction, 9 were primary, 8 secondary forms, 2 FMF and 3 were mixed. type.