The phycocyanin with a purity of A620/A280=1.958 was extracted from Anabaena.This research focuse on the storage conditions in which the phycocyanin was used as the colouring agent for food,and the influence on the stability of the colouring agent for food applied by the storage conditions.The results demonstrated that;the temperature,sunshine and pH had certain influences on the phycocyanin as a colouring agent for food during its storage.The best condition in which the phycocyanin functions as the colouring agent for food lied in the following factors;the phycocyanin was storaged away from the light under lower temputure in pH neutral conditions.Different food colour agents have different level of influence on the phycocyanin.Sugar,benzoic acid,vitamin C,phycite can enhance the luster of the color,and ehanol,citric acid,potassium sorbate,inositol,magnesium sulfate,and sodium bicarbonate,sodium carboxymethyl cellulose can dothe opposite.