Experiments were carried out at Diarb Negim district, Sharkia Governorate to study certain piercing  sucking pests infestation and their associated predators on cucumber plants during two  successive seasons 2014-2015 and 2015-2016  . The dominant insect pests were cotton aphid, Aphis gossypii Glover, whitefly, Bemisia tabaci (Genn.), Thrips tabaci  (Lindquist) and a few numbers of Jassid as well as Nezara viridula  F. Whereas, the prevailing associated predators were Orius   spp.,   Metasyrphus corollae F., Chrysoperla carnea (Steph.), Coccinella undecimpunctata L. and a few number of Paederus alfierii (Koch) and true spiders.  The infestation with A. gossypii  and B. tabaci  were much higher in autumn plantations than in summer plantations in both seasons of study, while, T. tabaci could be detected in few number  on cucumber plants during autumn plantation in both seasons. In autumn plantation, Orius spp. had two peaks of activity in both years. The two peaks were recorded on the 1st and the 3rd   November (17 and 23 individuals/30 leaves, resp.) in 2014 season and (9 and 12 individuals/30 leaves) in 2015 season. In the same regards, during summer plantation, Orius spp. had two peaks of activity on the 2nd of May and the 1st of June   (48 and 31 individuals/30 leaves) in2015 season. Also, Metasyrphus corollae had two peaks of activity on 4th of April and 1stof May (3 and 17 individuals/30 leaves. Chrysoperla carnea had two peaks of activity on 2^nd and 4th of May (3 and 15 individuals/30 leaves).Statistical analysis showed that temperature and relative humidity were significant with some insects and insignificant with the others.