Abstract: For the purpose of improving the application character of pea protein isolate(PPI)emulsions at acidic conditions,the emulsions oil-in-water(O/W)was stabilized by complex at acidic conditions,the complex was informed by interactions between PPI and carboxymethylcellulose(CMC). Primarily,the solubility and surface hydrophobicity of PPI(3%)were studied with increasing of CMC concentration(0~0.5%). And on this basis,the effects of PPI-CMC complex were analyzed on the ζ-potential,droplet size,viscosity,turbiscan stability index(TSI)and microstructure of emulsions. The results showed that while CMC concentration increased from 0 to 0.5%,the negative surface charges of the emulsion droplets were strengthened for which the absolute values of ζ-potential increased. At CMC concentration ≥0.4%,the stability of the PPI emulsions was efficiently improved,the droplets dispersed evenly in the systems and the flocculation phenomenon was reduced. After storage at 4 ℃ for one week,no visible separations were found in these systems. Therefore,the application character of PPI emulsions at acidic conditions can be effectively improved by regulating PPI-CMC interaction and the results are expected to provide references for the development of high pea protein acid dairy and beverage.