**Abstract**

Citrus fruit is one of the most important fruits all over the world. Citrus fruits are essential sources of food and energy and play a critical role in supplementing healthy diets. They contain vitamins A, E, and B (thiamine, riboflavin, and niacin), minerals, and antioxidants such as flavonoids, vitamin C, phenolic compounds, and carotenoids as nutrients present in them. Mineral nutrients are essential nutrients found in many different types of plant and animal-based foods. Macro-minerals are required in large amounts while trace minerals are needed in minute quantities such as iron, zinc, and copper. Potassium is a vital nutrient in citrus fruit which regulates fruit size, fruit appearance, fruit color, and vitamin content. Fresh size and mass, percentage of rind and juice, soluble solids content (SS), titratable acidity (TA), SS/TA ratio, and industrial yield, expressed in kg of sugar per 100 kg of processed fruit or SS per box (40.8 kg) are used to evaluate fruit quality in citrus fruits. The amount of potassium below 0.4% affects tree development; otherwise, over an extensive range of variation does not generally affect plant growth. Potassium is one of the abundant elements in citrus fruits that affect both yield and quality. This chapter reviews the role of mineral nutrients in citrus production and the roles play in the human body.

**Keywords:** mineral nutrient, citrus fruit, Potassium, Nitrogen, macronutrients
