The aim of this study is to evaluate the effect of ceramic repressing on marginal chipping of two different pressable ceramic materials. Materials and Methods: Two commercially available glass ceramic materials were used in this study; IPS E-max press (Ivoclar, vivadent) and Celtra press (Dentsply, Sirona). The two materials were used to fabricate veneer samples as which a total of forty veneers were constructed .The samples for each material (n=20) were randomly divided into two equal groups; Group A: Pressed specimens (n=10) veneer shaped wax patterns were invested and heat-pressed according to the manufacturer’s recommendations and Group B: Re-pressed specimens (n=10) the leftover material from 1st pressing was recovered and the buttons were adjusted to fabricate the specimens by repeated heat-pressing using the same procedures as for (A). A stereomicroscope was used to measure the amount of marginal chipping of each veneer in microns (L). The chipping factor (CF) was calculated using the following equation: CF= L/P x 100, where (L) is the amount of marginal chipping and (P) is the marginal circumference of each veneer. A sharp conical head indenter was fixed on a universal testing machine (Instron, 3345, UK). Chipping factor were recorded and mean values for each group determined. Data was statistically analyzed. Results: For IPS E.max or Celtra press; there was no statistically significant difference between mean values of press and repress conditions (P <0.05) between tested groups. Chipping factor mean values was recorded for Celtra press (14±1.1) while E-max press was recorded (13.9±0.5), Celtra repress recorded (13.8±0.7), however E-max repress recorded (13.5±1) which have the lowest chipping mean value. Conclusions: The optimum properties for lithium disilicate Press ceramic materials are obtained with the first pressing. However, multiple heat repressing could affect the microstructure and mechanical properties but with no statistically significant difference on surface marginal chipping.