Syphilis is well known as a great mimic, however it is not recognized as a cause of cervical lymphadenopathy. We report a case of a 21-year-old man who presented with marked unilateral cervical lymphadenopathy. He had no evidence of oropharyngeal chancres, skin or genital lesions. Computed tomography (CT) and magnetic resonance (MR) images showed multiple cervical lymphadenopathy, and serologic tests for syphilis were positive. Syphilis should still be a factor for consideration in the differential diagnosis of cervical lymphadenopathy.