Aim : The aim of the study was to assess the modified polycaprolactone resorbable membrane in horizontal ridge augmentation of atrophic ridge. Subjects and Methods: Twenty Patients with alveolar bone resorption in the anterior maxilla that require alveolar ridge augmentation to allow rehabilitation with fixed implant-supported prosthesis were included in this study. Patients were divided randomly into two main groups; Group (A) to whom collagen resorbable membrane has been used. Group (B) to whom modified (PCL) resorbable membrane has been used. Results: In the present study, At 1 week, after 1 as well as 3 months; there was no statistically significant difference between Local infections, wound healing, and membrane exposures in the two groups. Immediately; there was no statistically significant difference between bone density measurements in the two groups. After 6 months, group (B)showed statistically significant higher mean bone density and ridge width than group(A) due to the flexibility present in the nature of the product used in group (B) that was not available in the product used in group (A). Conclusion: PCL has been introduced as candidate materials for bioactive GTR membrane due to its biocompatibility and simple fabrication procedure. PCL-membrane promote tissue formation.