experiments were carried out to study the effect of insect infestation by gladiolus thrips, Thrips simplex ( Morison ) on the vase life period of gladiolus flowers after picking under glasshouses condition and flowers contents specifically two elements (sugar and protein) which correlate with vase life period. Morevore effect of infestation with this insect on the interior tissues of the gladiolus flowers petals was also conducted. Experiments were done in El-Orman garden, Giza Governorate throughout season 2014. The vase life period of the infected gladiolus flowers withT.simplex ranged from between 3-5 days while the vase life period of non-infected flowers ranged between of 7-9 days. Results indicated that the total soluble sugar and total protein were significantly lowerin different flowercolures of gladiolus (yellow, red, pink and white) infested with gladiolus thrips, T. simplex compared with control. Also, results showed that there werechanges in protein banding patterns in petals of gladiolus flowers corresponded with infectionby T. simplex.