Purpose: The purpose of the current study was to evaluate the fatigue resistance of zirconia reinforced lithium silicate (VS) and hybrid ceramic (VE) occlusal veneers, with two different thicknesses. Materials and Methods: twenty extracted human maxillary first molars were prepared to replicate worn occlusal table. Samples were distributed into two groups according to the received occlusal veneers material; Vita Suprinity and Vita Enamic, each group was further subdivided into two subgroups according to the thickness of the occlusal veneers (0.6mm or 1.2mm). The samples were cemented by self-adhesive resin cement. Samples were subjected to step fatigue resistance test, Assessment of fracture mode was evaluated. Results: The higher mean fatigue resistance values were recorded in Vita Suprinity compared to Vita Enamic occlusal veneers. The higher mean fatigue resistance values were recorded in 1.2 mm compared with 0.6 mm thickness. The mean fatigue resistance value was non –significant at the interaction of groups and subgroups variables. Conclusions: Thin (1.2mm) and ultra-thin (0.6mm) Vita Suprinity and Vita Enamic can be used to construct occlusal veneers in terms of fatigue resistance values.