Abstract: Zein, a natural biopolymer, has attracted significant attention in the fields of food, medicine and environmental engineering due to its amphiphilic nature, biocompatibility and biodegradability. This paper presents a systematic review of the preparation strategies, structural regulation mechanisms and recent applications of zein-based particles, emulsions, fibers and composite materials, structured around the theme of “structural properties-preparation technologies-multi-field applications.” Special emphasis is placed on the functional properties-such as antibacterial, controlled release and adsorption-of zein materials constructed via anti-solvent precipitation, pH-driven assembly, electrospinning and composite methods. Furthermore, current research limitations are discussed and future directions are proposed, including a focus on molecular self-assembly mechanisms, development of smart responsive materials and optimization for industrial application, with the aim of supporting the transformation of zein from laboratory research to industrial practice.