Endocrine-disrupting chemicals (EDCs) often show their effects through steroid hormones or peptide/protein hormones, and they can disrupt any aspect of hormone activity. It is stated that EDCs not only affect endocrine function, but also negatively affect immune system function. They can affect immune function either directly through the action on immune cell surface receptors or indirectly through other physiological mediators. Exposure to EDCs typically impairs immune functions, either by suppressing immunity and increasing susceptibility to infections, or by enhancing the immune response, leading to inflammation, allergies, or autoimmune diseases. EDC-mediated immunotoxicity is an important human health concern, as long-term immune dysfunction increases the risk of many communicable and non-communicable diseases. The effect of EDCs on the immune system has largely been studied in the context of allergies and autoimmune disorders. It shows that EDC exposure results in an imbalance in oxidative stress, pro-inflammatory and anti-inflammatory immune responses and consequent increase in inflammation. The dose, duration, route of exposure to these toxins, age, sex of the individual, microbiota status, and other environmental conditions (such as stress, diet, or concomitant exposure to other toxic substances) can also change their effects on immunity. In this chapter, the effects of some EDCs on innate and adaptive immune system cells and the development of inflammation are discussed.