An extractive spectrophotometric method for the determination of cyanide in wastewater is developed. Cyanide is reacted with bromine to form cyanogen bromide, which subsequently reacts with pyridine. Glutaconic aldehyde is formed through the heterolytic cleavage of pyridine ring, which is then coupled with 4-amino salicylic acid. A yellow orange dye formed in alkaline medium is extractable in n-butanol in acidic medium. The extract shows absorbance maxima at 520 nm. The system obeys Beer's law in the range of 0.03-0.20 mu g/mL. Important analytical parameters such as time, temperature, reagent concentration, acidity etc. have been optimized for complete colour reaction. Sandell's sensitivity and molar absorptivity for the system have been calculated. The method has been successfully applied for determination of cyanide in wastewater and biological fluid.