Background: Oral rehabilitation entered a new era with the creation of osseointegrated dental implants. The excellent success rate and long-term follow-up (more than 20 years) of patients treated with osseointegrated dental implants are of interest to clinicians and researchers worldwide. The present study was conducted to assess three-dimensional finite element analysis of effect of abutment materials on stress distribution around peri-implant bone in immediate and delayed loading conditions. Materials & Methods: Six abutment groups were loaded from vertical, horizontal, and oblique directions. Group I had zirconia with delayed loading (DL), group II had Polyether Ether Ketone (PEEK) with DL, group III had Titanium grade extra low interstitial (ELI) with DL, group IV had zirconia with immediate loading (IL), group V had PEEK with IL, and group VI had titanium grade ELI with IL. Using the finite element approach, von Mises and main stress analysis was performed on the implant and the peri-implant bone. Results: Group II, or PEEK customized abutment with titanium implant, had the highest maximum and lowest stress values in the cortical bone. Group III, or titanium grade ELI abutment, came in second, and group I, or zirconia customized abutment assembly, had the lowest value. Group I had the highest maximum and lowest stress values in the cancellous bone, followed by group III, while group II had the lowest value. Group V—the PEEK customized abutment with titanium implant—acquired the highest maximum and lowest stress values in the cortical bone. However, group IV had the highest maximum and lowest stress values in the cancellous bone, followed by group VI, and group V had the lowest value. Conclusion: The stress produced in the implant and the peri-implant tissue is impacted by changes in the abutment material. In both immediate and delayed loading conditions, PEEK abutments demonstrated noticeably less von Mises stress in the implant body than titanium and zirconia.