The white scale insect is one of the most dangerous pests that attacks the leaf crown of the date palm. It absorbs the sap of the palm tree which decreases the content of chlorophyll pigments, because the colonies of the white scale insect causes a reduction in the photosynthesis surface. Our objective is to study the effect of Parlatoria blanchardi on the content of chlorophyll pigments in leaflets according to several factors (orientation, variety of date and season) in a palm grove in Biskra (Algeria). In the laboratory, the harvested leaflets are used for the extraction of pigments, the resulting solution is placed in the spectrophotometer tank for dosing, and our results are processed using the Stat View software which allowed the calculation of the variance (ANOVA). Our result shows that the most infested direction is the east and then the north which are characterized by low pigment contents, since it is often exposed to direct sunlight and the prevailing wind. The Mech Deglet variety has a low amount of chlorophyll pigments because it is the most infested. The content of chlorophyll pigments is low during the spring season, when the white scale insect shows a high activity.