Autoinflammatory diseases (AIDs) are characterized by recurrent episodes of systemic and organ-specific inflammation. Many of these diseases share fever as a common presenting feature. Physicians need to consider AIDs in children with recurrent, unexplained fevers, when infectious and malignant causes have been discarded. This article discusses the differential diagnosis of recurrent fever in children, with a focus on AIDs. It discusses pharyngitis, and cervical adenitis and the monogenic autoinflammatory diseases that cause recurrent fevers including familial Mediterranean fever, hyper-immunoglobulin (Ig) D and periodic fever syndrome, tumor necrosis factor receptor–associated periodic syndrome, cryopyrin associated periodic syndromes, deficiency of interleukin-36 receptor antagonist, Majeed syndrome, chronic atypical neutrophilic dermatosis with lipodystrophy and increased temperature syndrome, and deficiency of the interleukin-1 receptor antagonist. In addition, the granulomatous disorders, pyogenic sterile arthritis, pyoderma gangrenosum, and acne and Blau syndrome, will be discussed.