Purpose: The aim of this study was to investigate the effect of type of bleaching material on the bond strength of ceramic veneers to bleached enamel.The effect of time interval between bleaching and laminating the tooth was also evaluated.Materials and methods: Thirty freshly extracted humanmolars were collected and sectioned mesio-distally to obtain (Buccal and Lingual) coronal halves. The samples were classified according to the type of tooth surface treatment into three groups: Control (no bleach), In-office bleach and at home bleach. Each group was subdivided into two sub groups: bonded after 1 week and after 4 weeks. Then further subdivided into two divisions: Non thermocycled and Thermo-cycled. After bleaching, teeth were prepared to accommodate veneers of equal thickness. IPS Empress 2 was used for veneer construction and luted with Rely X cement. Specimens were then subjected to shear forces. Student’s t-test was used to compare between non-thermocycled and thermocycled specimens as well as to compare between the two time periods. One-way ANOVA was used to compare between control, in-office and home bleaching techniques.Results: unbleached control group had significantly higher bond strength than the bleached groups regardless the concentration of the bleach. Also showed that there was no significant difference between the two concentrations(10% and 35%) they both showed significantly lower bond strength than control regardless of the time elapsed.In addition, the results showed that the in office bleach (35%) whether thermo-cycled or not, the 4 weeks period showed significantly higher bond strength than 1week, unlike the home bleach (10%) where the non thermocycled show no significant difference between the 2 time periods while the thermo-cycled group the 4 weeks had higher significant bond strength than the 1 week. Lastly, the study showed that the non thermo-cycled groups showed higher mean micro-shear bond strength than the thermo-cycled groups.Conclusion:Bleaching the enamel has an adverse effect on the efficacy of bonding between enamel and luting composite resin.Home bleached showed better bonding to bleached enamel than In-office bleach.4 week delayed bonding procedure after bleaching improved the efficacy of bonding veneers to bleached enamel