Chilli peppers (Capsicum spp.) are globally significant not only as culinary ingredients but also as functional foods rich in nutrients and bioactive compounds. This chapter explores the nutritional and health-promoting potential of chilli peppers by examining their macronutrient and micronutrient profiles, capsaicinoid content, pigment composition, and associated antioxidants. Chilli peppers are valuable sources of vitamins (notably vitamin C, E, and provitamin A), minerals, and dietary fibre. Capsaicinoids, popular for characteristic chilli pungency, also offer notable pharmacological benefits including analgesic, anti-inflammatory, and metabolic-modulating effects. The chapter also delves into the diverse chilli pigments such as carotenoids, anthocyanins, chlorophylls, and flavonoids, which not only define the fruit’s vivid colouration but also contribute to antioxidant and health-protective functions. Factors such as genotype, maturity stage, environmental conditions, and postharvest handling significantly influence the content and bioavailability of these compounds. A comprehensive understanding of the nutritional and functional attributes of chilli peppers would necessarily also encompass their importance in human nutrition as well as nutraceutical development.