Abstract: Walnut oil is a valuable woody grain oil with high nutritional content and excellent health function activity, but it is susceptible to issues such as oxidative deterioration. The chemical composition and manner of production of walnut oil have a considerable influence on its oxidative stability. The types, content, and functional effects of fatty acids, phenolic compounds, phytosterols, squalene, and other components in walnut oil are discussed in this article. It also investigates walnut oil's anti-inflammatory, antioxidant, antitumor, immunoregulatory, neuroprotective, and other biological activities. It examines the benefits and drawbacks of conventional extraction methods and technical advancements, as well as the influence of walnut oil chemical composition and preparation methods on oxidative stability. In addition, possibilities for walnut oil research directions, such as functional activity, efficient preparation technology, and suitability for processing specific types are created in order to provide a reference for the development and utilization of walnut oil products.