The aim of this study was to evaluate implant stability and the peri-implant marginal bone loss around two different threads design implants; conventional macro-threads design implants and crestal micro-threads design implants. Materials and methods: A total of 14 implants of 3.5 mm diameter × 11.5 mm length having two different threads designs were divided into two groups, (n = 7): group A; implants with conventional macro-threads design and group B; implants with crestal micro-threads design were placed in maxillary permolar area in partially edentulous patients. Stability was evaluated by insertion torque and resonance frequency using an Osstell device at baseline (time of implant insertion),15, 30, 45 and 60 days follow up periods, while peri-imlant marginal bone loss was measured by CBCT taken at baseline (time of implant insertion) 3, 6,12 and 18 months (one year after loading) follow up periods. Results: At the end of follow up period, group B (Implants with crestal micro-thread design) showed statistically significant higher mean values regarding primary and secondery implant satbility inaddition to statistically significant lower mean values regarding peri-implant marginal bone loss when compard to group A ( implants with conventional macro-threads design) . Conclusion: Implants with crestal micro-thread design showed better stability and less peri-implant marginal bone loss than the conventional macro-threads design implants.