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The effect of storage‏‏ temperature, pH and light on the stability of anthocyanin pigments of two varieties of grapes (Vitis vinifera)‘Tobrehghareh’and ‘Rishbaba’in the aqueous extract was studied and compared the stability of anthocyanin pigments of four varieties of grape (‘Ghezel’,‘Rishbaba’,‘Tabarzeh’and ‘Tobrehghareh’). An anthocyanin extract was prepared by treating grape filter trim with absolute ethanol (100%) acidified with 0.1% hydrochloric acid. The extract was concentrated to provide an aqueous extract for testing as a colorant for aqueous solution. The concentration of anthocyanin pigments in the aqueous extract was determined by spectrophotometer at 520 nm on samples diluted with pH 1.0 and 5.0 buffers. The results on the ‘Tobrehghareh’and ‘Rishbaba’varieties of grape showed that increasing the storage temperature of aqueous extracts from 5 to 35 0 C, accelerated greatly the pigment destruction. Increasing the pH of samples also from 2 to 6 accelerated the pigment destruction in the aqueous extract. In the aqueous extracts, light in comparison whit dark also increased the destruction of pigments. Anthocyanins from ‘Ghezel’were much more stable than other varieties of grape where compared at pH 2 and room temperature. Such increased stability was attributed to their intrinsic nature.