The effects of dietary fiber (DF) and ferulic acid (FA) on the aggregation of Glutenin macropolymer (GMP) were studied by measuring the protein particle size distribution， molecular weight distribution and subunit changes during dough resting； At the same time， the interactions between dietary fiber or/and ferulic acid and GMP protein molecules were explored by fluorescence spectrum， ultraviolet spectrum and free amino content. The results showed that during the dough resting process， GMP aggregated from small particle size (<11 μm) into large particle sizes (>50 μm). FA depolymerized the glutenin subunits in the high molecular weight range. DF+FA reduced the impact of this depolymerization on the GMP molecular weight distribution and maintain the subunit ratio at 0.25. Fluorescence spectra and ultraviolet spectra showed that FA exposed the protein structure segments containing tryptophan and tyrosine residues to a more polar aqueous environment. The content of free amino groups in protein molecules might be significantly reduced (P<0.05) by 22.48% and 17.38% respectively (when the dough resting for 90 min) through covalent cross-linking between DF/FA and GMP， resulting in changes in protein structure. Conclusion: The addition of DF and FA had an impact on the molecular aggregation of GMP proteins， and generated intermolecular interactions with GMP proteins， resulting in changes in the structure of GMP.