Experiments were carried out to study the comparison between the effects of insect infestation by the aphid, Myzus persicae (Sulz.) (Homoptera : Aphididae) and thrips, Thrips tabaci Lind.(Thysanoptera: Thripidae) on some morphological characteristics of tulip (Tulipa sp. Fam. Liliaceae) flowers under glasshouse conditions at two locations (governorates) Cairo Governorate and Giza Governorate throughout 2017-2018 seasons. Morphological characteristics which studied were: color of the flower, number of the petals per flower, the flower diameter, the weight of the flower, the stem length, vase life and annual production. Results showed that the infestation by aphid and thrips affected all morphological characteristics except the color of the flowers. And the effect of infestation by aphid was more than the effect of infestation by thrips, this is compared to control (tulip flowers which did not infest by the two studied insects). Also, the present study showed that the effect of aphid and thrips infestation concentration on the vascular bundles of the flowers petals, and with the increase in the infestation by the two insects the damage in the vascular bundles increases