This study aimed to estimate the effect of using two different attachments on the marginal bone height changes and implant stability of immediately placed and immediately loaded implant in mandibular overdenture cases. Twenty male patients were selected to share in this study from the out-patient clinic of prosthodontic department, faculty of Dentistry, Ain Shams University with age range between 55-65 years, having two standing mandibular canines with compromised prognosis and opposing completely edentulous maxilla. The patients were randomly divided into two groups , Group I: Patients were rehabilitated with two immediately placed implants in bilateral canines, immediately loaded and retained with ball and socket attachments, Group II: same but with locator attachment. Implant stability was measured using Osstell mentor. Radiographic evaluation using parallel technique (Digora software) was done. there was statistical non significance difference in the marginal bone loss throughout the follow up period (P>0.05). On comparing the two groups regarding implant stability there was statistical non significance difference immediately postoperative and through the follow up period (P>0.05). Within limitation of this study, it could be concluded that both types of attachment (ball and socket and locator attachment) are effective attachments for immediately placed and immediately loaded implants as a line of treatment of mandibular overdenture. Where there was statistical insignificance difference regarding marginal bone loss and implant stability between the two attachments.