Seasonal abundance, generations and horizontal distribution of Parlatoria ziziphi (Lucas) were carried out on mandarin trees at the Faculty of Agriculture in Shebin El-Kom, Menoufia Governorate during two successive years (2017-2018 and 2018-2019). The obtained results revealed that the total numbers of alive stages had two peaks of activity during the first year (2017-2018) they took place in September and January while, during the second year (2018-2019) three peaks of activity were recorded in September, January and March. Also, the insect had three annual generations on mandarin trees the generation duration varied from three to five months. The horizontal distribution showed that the insect and its associated parasitoids Aphytis sp. concentrated in the quarter of the trees' north eastern direction. The effects of some weather factors on P. ziziphi and its associated parasitoids were studied.