The pomegranate whitefly, Siphoninus phillyreac (Haliday) (Homoptera: Aleyrodi­dae), is the main drastic pest of pomegranate in Egypt (Abd-Rabou, 1998). Pomegran­ate leaves heavily infested with S. phillyreac do not cope with requirements for normal fluid transport and proposed photosynthesis. The loss and damage of phloem fluids add a loss of potential productivity and probably contribute to the reported reduction in fruit size (Costacos, 1963). Abd-Rabou (1997a) in Egypt recorded this species on four host plant species, apple (Pyrus malus L.), pear (Pyrus communis L.), Quince (Pyrus cydonia) and pome­granate (Punica granatum L.). While Mound and Halsely (1978) in the world recorded 20 host plant species including olive attacked by this pest. During December 2002, collected olive leaves heavily infested by whitefly spe­cies in El-Arish region (North Sinai) were transferred to the laboratory for identification. Identification followed mounting the specimens through the method of Abd­Rabou,1997b. Identification started by the key of the economic important whitefly pests of the world by Martin (1978) followed by the key of Egyptian species of white-flies (Abd-Rabou, 1997b).Results indicated that the species collected was the pomegranate whitefly, S. phillyreae. This is tho first record for this pest to represent on olive as a new host plant of S. phillyreae in Egypt.