Abstract: Wheat gluten protein, consisting of glutenin and gliadin, is a key component that determines the processing characteristics of wheat-based products. Dietary polyphenols have attracted increasing attention due to their antioxidant, anti-inflammatory, and other bioactive properties, and they are prone to interacting with gluten proteins in food systems. The interaction can alter the structural and functional properties of gluten, thereby significantly affecting food processing performance and nutritional value. This paper focuses on the interaction mechanisms between dietary polyphenols and gluten protein and elucidates their effects on the structural and physicochemical properties of gluten. In addition, recent advances in analytical methods for characterizing their interactions, as well as the applications of polyphenol–gluten protein complexes in food processing and novel material development, are reviewed.