Mango (Mangifera indica L.) is an intensively cultivated fruit in Mexico, the leading exporter of this product in the world. One important limiting factor in mango production is the white mango scale (Aulacaspis tubercularis Newstead; Hemiptera: Diaspididae). White mango scale infestation causes irreversible leaf yellowing and death, and it lowers fruit quality below export requirements. Feeding mechanisms of these diaspidids have not been extensively studied; no histological studies on this subject are known. We histologically analyzed leaf tissues penetrated by the stylet bundle (SB) of white mango scale females, in order to follow the SB cellular path, to observe the extent of visually-detectable leaf cell damage, and to determine if this insect feeds on phloem sap. Mango plants of cv. ‘Manila' were artificially infested with this insect in the laboratory. Histological slices from infested leaves were processed for microscope observation of the intact SB. Through this process a complete SB could not be observed, so its full accurate length could not be reported. However, the SB length was estimated at 3 mm, i.e., 3 times the total length of the female body length, which was 1 mm. The SB path inside the leaf was mostly intracellular through the mesophyll, but it also pierced lignified xylem cells and nutrient-rich phloem tissues in the vascular bundles. Thick red masses were formed along the SB path, possibly containing phenolic compounds. Cell lysis or collapse was not observed in the SB-injured leaf tissue.