Soybean plants are subjected to attack by piercing-sucking in‌sect pests causing severe damage. The interactions between insects and their natural enemies are essential ecological processes that contrib‌ute to the regulation of insect populations. So, the present investigation was conducted to study the population density of aphids, Aphis spp., whitefly, Bemisia tabaci (Genn.), thrips, Thrips tabaci (L.) and jassids, Em‌poasca spp. on soybean in relation to common associated predators (Paederus afferii Koch., Chrysoperla carnea Steph, Coccinelfa undecim‌punctata L. and Scyminus spp.) and some prevailing climatic factors (temperature, relative humidity and wind speed) during two seasons (1992 and 1993). Obtained data indicated the following: 1.The populations of the considered insect pests and associated preda‌tors were higher in the second season than in the first one. 2.Every insect pest had one abundance peak which incoincided with the others. 3.It was appeared that the whitefly, thrips and jassids had one genera‌tion a season. While, two generations of aphids were detected. 4.Concerning the associated predators, their total population peaked twice annually. The first peak appeared in the second half of July for the two tested seasons while, the second peak appeared on Sept. 27 for 1992 season and on Sept. 6 for 1993 season. 5.The combined effect of the weekly mean of predators population, dai‌ly mean temperature, relative humidity and wind speed was responsi‌ble for 84.76, 73.9, 68.70 and 58% of changes in the populations of jassids, thrips, whitefly and aphids, respectively in the first season, while it recorded 79.40, 54.80, 66.30 and 45.8%, respectively in the second one. Such results are important in enlightening integrated control of these sucking insects.