The presented work was carried out in a grapevine farms, at Fayoum Governorate, to shed the light on seasonal fluctuation at the population density of the striped mealybug, Ferrisia virgata Cockerell and the pink hibisicus mealybug, Maconellicoccus hirsutis Green (Pseudococcidae: Homoptera) as well as the effects of the main weather factors on the two insect population. Regular biweekly samples were taken for two successive years, from Nov. 2015 to Oct. 2017. The results indicated that all counted stages of the striped mealybug, F. virgata in the first season had two peaks on leaves of grapevine; 1 st peak was recorded at the end of Aug. and 2 nd one was recorded at the end of Sep. Regarding bunches of grapevines, only one peak was recorded in the first season at the end of Sep., in the second year, two peaks were recorded; the first peak was recorded at end of Jul. and the second one was recorded at the end of Aug.. The population of M. hirsutis nymphs recorded one peak 130 nymphs/10 bunches at end of Sep.. Also, adult females recorded one peak at end of Aug. with 53 adult females/ 10 bunches while the total population of the mealybug recorded two peaks (in mid- Aug. and end of Sep.) to record 58 and 133 individuals/10 bunches. The results indicated that maximum and minimum temperatures had negative insignificant effects on nymphs, while showed positive insignificant effect on adult females and all individuals.