The article reviews the response of plant secondary metabolites (SMs) to various environmental factors, including light irradiation, temperature, soil water, soil fertility, and salinity. SMs, which are not essential for plant survival but play crucial roles in defense against pathogens and environmental stresses, are increasingly used in medicine, food additives, and industrial applications. The review highlights how these environmental factors influence the biosynthesis and accumulation of SMs, with each factor affecting the content and type of SMs produced. For instance, light duration and intensity can significantly alter the levels of phenolic compounds and flavonoids, while temperature can enhance or reduce the production of different SMs depending on the plant species and the specific compound. Soil water stress can increase SMs in some plants, particularly under drought conditions, but can also decrease their content in others. Soil salinity can stimulate the production of phenolic compounds and alkaloids, but the effect varies with the plant species. Soil fertility, particularly nutrient deficiencies, can influence the concentration of flavonoids and alkaloids. The review provides a comprehensive overview of how environmental factors interact with plant metabolism to produce diverse SMs, offering insights into optimizing cultivation techniques to maximize the yield and quality of bioactive compounds in plants.The article reviews the response of plant secondary metabolites (SMs) to various environmental factors, including light irradiation, temperature, soil water, soil fertility, and salinity. SMs, which are not essential for plant survival but play crucial roles in defense against pathogens and environmental stresses, are increasingly used in medicine, food additives, and industrial applications. The review highlights how these environmental factors influence the biosynthesis and accumulation of SMs, with each factor affecting the content and type of SMs produced. For instance, light duration and intensity can significantly alter the levels of phenolic compounds and flavonoids, while temperature can enhance or reduce the production of different SMs depending on the plant species and the specific compound. Soil water stress can increase SMs in some plants, particularly under drought conditions, but can also decrease their content in others. Soil salinity can stimulate the production of phenolic compounds and alkaloids, but the effect varies with the plant species. Soil fertility, particularly nutrient deficiencies, can influence the concentration of flavonoids and alkaloids. The review provides a comprehensive overview of how environmental factors interact with plant metabolism to produce diverse SMs, offering insights into optimizing cultivation techniques to maximize the yield and quality of bioactive compounds in plants.