The currant study was carried out at one of the most important regions of Egypt (Saint Katherine Protectorate, South Sinai) during the period from September 2008 to September 2009. The currant study aimed to estimate and assess the biological diversity of gall insects in SKP assimilated by the twenty one chosen localities. The study also aimed to investigate the impact of different ecological factors, such as altitude, vegetation cover on the temporal and spatial distribution of insect galls. Gall inducers' diversity in SKP was calculated according to Simpson diversity index that clarified the high diversity of these gall inducers in SKP. Insect galls were found on ten plant species belonging to 8 families in SKP. Every host plant species may has one or more parts that are subjected to gall formation. Different ecological factors, such as altitude, vegetation cover were affected the temporal and spatial distribution of insect galls.