Objectives: To assess the influence of lab composite, pressable glass ceramic and zirconia ceramic on the fracture resistance of maxillary premolars with inlay preparation. Materials and Methods: Forty sound maxillary premolars were divided randomly into four groups of 10 teeth each. Teeth in the first group were left intact. Teeth in the remaining three groups were prepared with inlay cavities and restored with lab composite (SR Nexco), pressable glass ceramic (IPS e.max Press) and zirconia ceramic (ICE Zirkon). The restorations were cemented with a total-etch, dual-curing luting composite (Variolink N). All specimens were subjected to thermocycling at temperatures of 5°C ± 2°C and 55°C ± 2°C for a total of 5000 cycles, then subjected to a compressive load in a universal testing machine using a metal sphere until fracture occurred. The results were analyzed by One-way ANOVA and Tukey HSD tests. The level of significance was set at P < 0.05. Results: No statistically significant difference was found between the means of control group and group restored with zirconia ceramic inlay restorations (P = 0.660). However, statistically significant differences were found between the means of control group and groups restored with lab composite inlay and pressable glass ceramic inlay restorations (P < 0.05). Conclusions:Lab composite inlays could not restore the original strength of weakened teeth owing to cavity preparation. While, ceramic inlays showed a comparable strength when compared to intact teeth especially zirconia ceramic inlays.