Abstract: Effects of erythritol on structural and functional properties of pea protein isolate were investigated. The effects of erythritol on solubility,water holding capacity,surface hydrophobicity,UV and fluorescence spectroscopy of pea protein isolate(PPI)were explored using 1-naphthalenesulfonicacid-8-(phenylamino)-sodiumsalt(ANS),UV and fluorescence spectroscopy methods. The results revealed that the solubility of PPI increased firstly and then decreased gradually when treated with increasing erythritol,and all reached minimum value at pH4.0. Water holding capacity increased gradually and all reached minimum value at pH5.0. Foamability and emulsifying properties of PPI increased first and finally reached equilibrium. Surface hydrophobicity increased gradually within 0-10% of PPI mass fraction,and finally became stable. With the increase of PPI mass fraction,tryptophan residues were further exposed and fluorescence intensity increased at first and subsequently stabilized,exhibiting a positive correlation with surface hydrophobicity. The research showed that appropriate erythritol treatment could improve the structural and functional properties of PPI.