Our understanding of autoimmune diseases has progressed tremendously in the past 20 years. Estimates of the prevalence of autoimmune diseases in the population may be 4% or higher. It is evident that heavy metals present serious risk to human health. Heavy metals are capable of altering the immune response; they have been implicated in influencing autoimmunity. In fact, they are usually inhibitory to immune cell proliferation and activation. This paper reviews the possible mechanisms which may play a role in metal-induced autoimmunity. A better understanding of these interactions remains a priority for the future.