Field experiments were conducted in Assiut Governorate during two successive seasons 2018 and 2019; to survey the phytophagous pests inhabiting squash plants, in addition, to study the relationship between the main pests namely; melon aphid, Aphis gossypii (Glover); whitefly, Bemisia tabaci (Genn.); two-spotted spider mite, Tetranychus urticae Koch; Onion thrips, Trhips tabaci (Lind.) and green leafhopper, Empoasca decipiens (Paoli) and its infestation of the winter, summer and nili squash plantations during 2018 and 2019 growing seasons.
            The results revealed clearly twenty species of phytophagous pests belonging to twelve families and seven orders inhibiting winter, summer, and nili squash plantations were encountered by using the plant samples method. Data also, revealed that the summer squash plantation received a higher average number with the aforementioned main pests, followed by nili and winter squash plantations; also, the whitefly, B. tabaci ranked first in the highest average number of individuals followed by a two-spotted spider mite, T. urticae; green leafhopper, E. decipiens; melon aphid, A. gossypii, and onion thrips, T. tabaci infestation to winter, summer and nili squash plantations during 2018 and 2019 growing seasons.
            It can be concluded that severe injury of the main pests; A. gossypii, B. tabaci, T. urticae, T. tabaci and E. decipiens to the squash plants can be avoided by using the winter plantation date followed by nili and summer plantation dates.