Yoga poses work both at cellular and molecular levels to boost immunity system of our body. NF-kB system is the master regulator of our immunity. Yoga exercise inhibit NF-κB signaling at various control points to enhance immune system. Thymus gland is responsible for building strong immune system. Proper yoga exercises strengthen and stimulates the thymus activities. Dynamic yoga poses are the best way to improve immunity. Exactly how yoga poses and breathing exercises inhibit NF-KB activities and improve immunity is under scientific investigation. In this review we will focus on the yoga poses that have direct impact on immunobiology. Physical and mental stress increases the release of cortisol and adrenaline and decreases immune system’s ability to fight infection. However, moderate levels of yoga practices reduces the stress hormones and increases the immune system’s ability to fight against infections like cold and flu.Most of the decline in immune system function is a direct result of degradation of the thymus gland. The shrinking of the thymus gland with age, resulting in changes in the architecture of the thymus and a decrease in tissue mass. Thymus gland is the master of the hormones and the immunity booster. Yoga stimulates the thymus gland which builds immunity and massages the lungs, heart, bronchial tubes. Yoga practice can help our cells to fight against harmful microorganisms and viruses by boosting our immune system, reducing stress and strengthening our body functions and systems. Here are five user-friendly yoga poses to increase your immunity.