The current studies were conducted on the field at kafr El-battikh reigon, Damietta Governorate. The K-186  tomato variety planted in two planting dates first of February and last of September during the two successive seasons 2016/17 and 2017/18 to determine the population abundance of the cotton mealybugs Phenococcus solenopsis (Tinsly). The highest peaks of abundance of P. solenopsis recorded in the February plantation during the two successive seasons 2016/17 and 2017/18 in the second week of April 2016 and the first week of April 2017 and represented by 279 and 351 indiv. /100 leaves, respectively. Meanwhile September plantation recorded the highest peaks of abundance during the two seasons in the first week of November 2016 and the last week of October 2017 and represented by 119 and 140 indiv. /100 leaves, respectively. The cotton mealybug P. solenopsis showed a significantly differences in the two plantations during the two successive seasons.