The population density of Macrotoma palmata F. (Coleoptera: Cerambycidae),attacking Navel orange trees, were monitored at Sharkia governorate during the two successive years 2012 and 2013. The activity seasonal fluctuation in M. palmata population on Navel orange trees started from the 2^nd half of May to 2^nd half of October 2012 or 1^st half of November 2013. Summer recorded the maximum flight (0.94-1.00 beetles/tree), followed by autumn (0.19-0.21 beetle/tree) and spring (0.08-0.10 beetle/tree), and stopped during winter. The total number of emerged beetles per year averaged 1.21-1.36 beetles / tree. It had one brood and there were 5.5 - 6 months of beetles' activity, yearly. The effect of weather factors on the borer activity was mostly positively significant with maximum, minimum, and daily mean temperatures, but negatively and insignificantly with day mean relative humidity. Number of emerged beetles was exeedigly doubled during only one year, thus should be highly considered in the integrated citrus pests control.