Manganese is an essential trace element in the metabolism of all living organisms, including plants and bacteria, and is found in all tissues of man. But manganese is also a potential carcinogen. 1 Among the inorganic chemicals, manganese, chromium, and selenium and certain organometallic derivatives of these metals have been found to be carcinogenic under special conditions and are also considered potential inorganic genotoxic agents. 2 The hazards of manganese have been known for a long time. The accurate determination of manganese in environmental and biological materials is of considerable importance for both metabolic and toxicological studies in humans and animals because of its dose-dependent harmful and benecial roles. Until recently, analytical techniques of satisfactory sensitivity and accuracy have not been widely available and attempts by many researchers to use unsatisfactory procedures have led to the publication of much **data** and also to biochemical conclusions of dubious value. 3 Clearly, major problems which have given rise to this situation are the very low concentrations of manganese in biological samples, and a lack of awareness of the need to exercise control over the extraneous contamination and interfering of foreign ions during all the steps of an analytical procedure. The present method that is being recommended over the existing methods almost in every respect in their own terms-selectivity, range of determination, accuracy, sensitivity, simplicity and rapidity of the operation, stability of the uorescent system and acidity of wide variation, etc.