Gelation and gel properties are crucial to surimi-based seafood products, and many factors significantly influence surimi gel quality. Although physical and chemical modifications can improve surimi gel performance, challenges such as high cost, difficulties in industrialization and environmental pollution pose significant barriers to their practicality. Natural additives offer a promising alternative by reinforcing and improving the characteristics of surimi gel through mechanisms such as protein conformational transformation, protein denaturation, and altered chemical forces. By incorporating different substances into surimi gel, it is possible to tune the interaction between the additives and the myofibrillar proteins, thus enhancing the gelation process and achieving the desired textural profiles. This review comprehensively explored the factors influencing the surimi gelation chemistry, with a focus on how the natural additives such as proteins, lipids, polysaccharides, salts, enzymes, and extracts impact the surimi gel properties. It elucidated the reinforcing mechanisms of these additives and proposed a general interaction model between natural substance and myofibrillar proteins. Furthermore, this review well established the interrelation between the performance and mechanism of enhancement effects of typical natural substances on surimi gels and provided new insights on tuning surimi gelation and gel properties by adding natural additives with specific physicochemical properties, thus facilitating the production of high-quality surimi products with satisfactory gel characteristics in food industry.