Ophionyssus natricis is a purely blood sucking parasite of snakes and of worldwide distribution. Infected snakes often exhibit lethargy, pruritus, crusting dermatitis,and behavioral changes. Ophionyssus natricis can also attack humans, causing popular vesiculo-bullous eruption of the skin. A 29 years old man working in zoo,Sari, Mazandaran, Iran, presented itchy papullar eruption of the skin. He had noticed small insects fixed on his skin and large numbers of these same insects on a python and its cage in the zoo. Regarding totheir morphological characteristics they were diagnosed as O. natricis (Geravis, 1844), a snake mite. It is the first report of O. natricis from Iran.