Paraneoplastic neurologic syndromes (PNS) are rare in pediatrics and are understood to be consequences of cross-reactivity against various neuroendocrine antigens expressed on cancer cells. Here, we report a case of autoimmune encephalitis, a type of paraneoplastic neurologic syndrome that was associated with a case of adrenocortical carcinoma and had some clinical response to immunosuppressive therapy. Adrenocortical carcinoma is a rare tumor with controversial tissue of origin but expresses various neuroendocrine antigens that could be the possible mechanism for this rare yet interesting association.