This study aimed to evaluate the fracture resistance of maxillary premolars with MOD cavities restored with recent composite types, and assess the biaxial flexural strength of those composites. MATERIALS AND METHODS: Sixty maxillary premolars were collected for fracture resistance (FR) evaluation of which ten were left intact (Group A).The remaining teeth received standardized MOD preparations. Forty teeth were divided into 4 subgroups (n=10) an``11```d restored with an assigned composite material; Subgroup B1 Filtek bulkfill posterior (3M ESPE). Subgroup B2 Ceram X Spheretec nanoceramic (Dentsply). Subgroup B3 Swisstec microhybrid (Coltene). Subgroup B4 Harmonize nanohybrid (Kerr). For group C, ten teeth were left unrestored after preparation. Fracture resistance test was done with the Universal Testing Machine (UTM) and failures were evaluated. For biaxial flexural strength (BFS) test, forty composite discs were divided into 4 groups, (n=10). Groups I, II, III and IV where discs made of (Filtek Bulkfill Posterior, 3MESPE), (Ceram X Spheretec, Dentsply), (Swisstec, Coltene) and (Harmonize, Kerr) respectively. Specimens were loaded till fracture using UTM. BFS was calculated and failures evaluated. RESULTS: FR values of Group A were the highest (1517.20), followed by Subgroup B2 (1179.00), Subgroup B4 (940.30), Subgroup B1 (813.70), Subgroup B3 (657.90) and Group C (559.50), with significant differences among the groups (p=0.001). BFS values were the highest in Group I (207.605) followed by Group III (165.241), Group IV (164.284) and Group II (151.221), with significant differences among the groups (p=0.001). CONCLUSION: FR of nanoceramic composite was significantly higher than all experimental groups, while microhybrid was the lowest with no significant difference with Group C. BFS of bulkfill composite was significantly higher than other groups, and that of nanocermic was the lowest. No direct correlation was found between FR and BFS of composite.