Purpose: The purpose of the current study was to assess fracture resistance and retention of three different endocrown materials. Materials and Methods: Thirty (n=30) sound mandibular molars were endodontically treated and according to endocrown constructed material appointed arbitrarily into 3 groups (n=10 each); Group (1): IPS e.max CAD, Group (2): Vita Suprinity and Group (3): Vita Enamic. Samples of each group were additionally subdivided into2 subgroups (n=5 each) according to fracture resistance and retention tests. Subgroup (A): Samples subjected to fracture resistance test and mode of failure. Subgroup (B): Samples subjected to retention test and mode of failure. The samples were thermocycled and seated on a universal testing machine and subjected to fracture resistance and retention test, then Data were statistically analyzed. Results: The highest mean failure load was recorded for Vita Suprinity endocrowns, followed by IPS e-max endocrowns, while Vita Enamic endocrowns recorded the lowest mean failure load.A non-statistically significant difference between the three tested groups of subgroup (A) revealed by using ANOVA test.The highest debonding load was recorded for Vita Enamic endocrowns, followed by IPS e-max CAD endocrowns, while the lowest mean debonding was recorded for Vita Suprinity endocrowns. A non-statistically significant difference between the three tested groups of subgroup (B) revealed by using ANOVA test. Conclusions: Endocrowns of Vita Suprinity showed higher mean failure load value compared to endocrowns of E-max CAD and Vita Enamic. While endocrowns of Vita Enamic showed higher mean debonding load value compared to E-max CAD and Vita Suprinity.