Abstract: To investigate the inducing effect of dielectric barrier discharge cold plasma (DBD-CP) technology (treatment voltages: 30, 90, 150 kV; treatment times: 30, 60, 90 s) on the conformational changes of whey protein isolate (WPI)-chitosan (CS) composite particles and its regulatory effect on the loading performance of anthocyanins (ACNs), this study employed a two-factor full factorial experimental design. By systematically evaluating the encapsulation efficiency (EE), loading capacity (LC), ζ-potential, and particle size distribution of the composite particles for ACNs, the optimal DBD-CP treatment parameters were screened. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), fluorescence spectroscopy (FS), and circular dichroism (CD) were utilized as multi-scale characterization techniques to deeply analyze the DBD-CP-induced molecular conformational changes in WPI-CS. Based on the results of the above systematic evaluation, the optimal DBD-CP treatment parameters were screened and determined as voltage 90 kV and time 60 s. Under this optimal parameter set, the EE and LC of ACNs increased to 91.93% and 4.59%, respectively, significantly higher than those of the untreated group (P<0.05); The ζ-potential increased, enhancing electrostatic repulsion between particles and significantly improving system stability; particle size analysis showed improved distribution uniformity and particle dispersibility. Structural characterization revealed that: Reactive species (e.g., electrons, ions) in DBD-CP promoted the exposure of hydrophobic groups in WPI and decreased the deacetylation degree of CS through oxidative modification, thereby enhancing the formation of hydrogen bonding and electrostatic cross-linking networks; simultaneously, the plasma etching effect optimized the pore uniformity of the complex, forming a dense encapsulation structure. DBD-CP treatment effectively modulated the structure of WPI-CS composite particles through synergistic effects (oxidative modification induced by reactive species and the etching effect), significantly improving their loading performance for ACNs and the system stability. This provides a theoretical basis for the application of cold plasma technology in stabilized delivery systems for bioactive components.