Fibromyalgia and chronic fatigue syndrome are disorders that often occur simultaneously and are characterized by widespread pain and persistent fatigue. The patients are associated with disability and impairment social and physical functions. There are many remedies in traditional Persian medicine suggested for management of the disease complaints. The aim of this study was to investigate the clinical presentations and pathophysiology of disorders with the basic and principal textbook of traditional Persian medicine written by Avicenna ( Canon of Medicine). According to Persian medicine, the term E'aya can be matched by mentioned disorders. Avicenna believed that strenuous activities play an important role in the beginning of some types of fatigue. He classified fatigue into 4 groups, and in each type the clinical symptoms varied. The multifaceted entity of fibromyalgia and chronic fatigue syndrome in Persian medicine and conventional medicine suggests multidisciplinary therapies in management of these disabling disorders.