Episodic fever is a difficult diagnostic challenge, more enigmatic than prolonged fever of unknown origin. Patients are younger, and have longer history of fever before admission. Despite the use of extensive diagnostic procedures 50% of the cases remain undiagnosed. A meticulous physical examination and history remains an important tool for registering potentially diagnostic clues useable in the diagnostic process. In the absence of clues, a staged diagnostic protocol can be used to search elements contributing to the diagnosis (laboratory investigations including chest X-ray and ultrasonography of upper abdomen, imaging techniques, endoscopies and histologic investigations. When diagnosis is not established and patient deteriorate, empiric therapeutic trial is started to presumptive diagnoses. If not, patient must be carefully followed as an out patient basis and symptomatically treated, periodic reassessment will in time reveal the development of overt disease.