Infectious agents have been implicated in the pathogenesis of many autoimmune diseases. Celiac disease (CD) is an autoimmune disorder affecting patients with a specific genetic predisposition (HLA-DQ2, HLA-DQ8) who are exposed to gluten, the major storage protein of wheat and similar grains. An environmental factor, such as an infectious agent, is thought to precipitate the disease via various pathogenic mechanisms, such as molecular mimicry, resulting in modulation of the host's immune tolerance. There is evidence that CD is related to perinatal infections, and that maternal-milk may have a protective role. Observations imply that there is a relationship between viral infections such as Adenovirus 12 and Hepatitis C virus and the development of CD. Understanding the relationship between infectious agents and autoimmunity may assist in prediction, early diagnosis and perhaps also the prevention of CD.