The classical clinical features of familial Mediterranean fever (FMF) are recurrent self-limited attacks of fever and serositis. Amyloidosis of the AA type is the major complication of the disease. The diagnosis of FMF is still based on a history of typical acute attacks, ethnic background, and frequently, notable family history. Together with the discovery of MEFV gene, the clinical criteria for the diagnosis of the disease did not change. Although we have learned a great deal about the clinical features and the pathogenesis of FMF in the past few years, many atypical cases emerge, and caution should be exercised during diagnosis. In this report, we present three FMF patients not fulfilling clinical criteria for the diagnosis, discuss rare and unusual presentations of the disease, and emphasize the role of genetic analysis in these suspicious cases.