Simultaneous bilateral facial paralysis (SBFP) is very rare, but it can present itself as the first complaint in a wide spectrum of diseases and a comprehensive evaluation must be completed. Bilateral Bell's Palsy can be diagnosed only when all other possible causes have been excluded. The prognosis and treatment for SBFP is dependent upon the underlying etiology. We present four cases of SBFP seen in our department which were finally diagnosed as leukemic infiltration, sarcoidosis, Bell's Palsy and demyelinating polyneuropathy (probably Guillain-Barré syndrome). The most important etiologies of the SBFP and the management of this entity are discussed.