The Maillard conjugate (MC))formed by Maillard reaction of sodium caseinate and oat β-glucan was used as the coating for stabilizing Zein. Composite LA-Zein-MC nanoparticles were prepared by anti-solvent co-precipitation method, with α-lipoic acid (LA) embedded in Zein as the core and Maillard conjugate as the shell. The study found that the optimum preparation conditions of composite nanoparticles were as follows: the mass ratio of Zein to α-lipoic acid was 25:1, and the mass ratio of Zein to Maillard polymer was 1:2.4. The prepared composite nanoparticles have a particle size of 235.4 nm, zeta potential of -32.1 mV and PDI of 0.144. The maximum encapsulation rate was 58.79%. The characterization methods of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X- ray diffraction (XRD) and differential scanning calorimetry (DSC) showed that the composite nanoparticles had smooth morphology and α -lipoic acid was embedded. Inside the composite nanoparticles, alpha-lipoic acid exists in an amorphous form. Stability measurement shows that the composite nanoparticles with this structure have high salt stability, pH stability and thermal stability. It has important reference significance for embedding and carrying hydrophobic active substances.