**Abstract**

Probiotics are host-compatible microorganisms that can optimally alter the balance of intestinal microflora, inhibit the growth of harmful bacteria, improve digestion, and increase the body's resistance by strengthening the immune system. Studies show that probiotics have antioxidant properties. Antioxidants are compounds that reduce the risk of various cancers and diseases. These compounds, in fact, inhibit the activity of free radicals and prevent their oxidation. By inactivation of free radicals, the body cells are protected from the destructive effects of these compounds. Oxidative stress is a condition that occurs as a result of disturbing the antioxidantprooxidant balance in the cell, which eventually leads to apoptosis and cell death. Consumption of probiotic strains with antioxidant activity can benefit human health by reducing oxidative damage. Since the use of probiotics helps hemostasis, improves immune responses, and prevents many disorders caused by oxidation in the host, in this chapter, we discuss the antioxidant effects of probiotics as functional foods.

**Keywords:** functional foods, antioxidant effects, probiotics
