Objective. We describe a case of autoimmune hypophysitis induced by the anticytotoxic T-lymphocyte antigen-4 (CTLA-4) agent, ipilimumab. Methods. Case presentation and review of the literature. Results. Autoimmune hypophysitis, a previously described rare disorder, is being recognized more frequently as a side effect of novel immunomodulatory agents used in the treatment of malignancies such as melanoma. CTLA-4 agents are associated with immune-related adverse effects (irAE) which occur as a result of activation (or lack of inactivation) of the immune response. This impacts not only malignant cells but also different host organ-systems. Autoimmune hypophysitis is one of several endocrinopathies associated with these agents. Conclusion. It is important that endocrinologists become familiar with the endocrinopathies, such as autoimmune hypophysitis, associated with new immunomodulator agents which are being used with increasing frequency to treat a variety of malignancies.