To investigate the physical and chemical properties of the green pigment in the green wheat,the pigment was extracted from the wheat bran by the percolation method with neutral ethanol and acidic ethanol.The extract was absorbed by the AB-8 type of macro-porous resin for purifying the pigment.The behavior of the rough pigment at different pH values was observed and their maximum absorption at ultraviolet and visible spectroscopy was detected.The results showed that the green pigment extracted by the acid ethanol was insoluble in neutral ethanol,the hue of the green pigment changed with pH values.The pigment was green in the acidic pH,nearly colorless in the neutral pH;brown-red with precipitates in the alkaline pH.The ratio of the absorbance of the maximum and secondary absorption peak of the pigment changed with different pH values as well.This indicated that the molecular structure of the pigment was changed with different pH values.The infrared spectrogram of the pigment and color reaction of alkaloid reagent indicated that it may contain amides structure.Based on the above results,the green pigment of green wheat might be alkaloids instead of anthocyanidin.