Background: Striae distensae are frequent undesirable skin lesions that result in considerableaesthetic concern. Successful treatment has always been challenging and several modalitiesare available, yet none of them is consistently effective and no single therapy is considered tobe pivotal for this problem. Laser has become a popular therapeutic alternative. The Role ofPlatelet rich plasma (PRP) in tissue regeneration and repair due to its high content ofbiological growth factors, has recently directed its therapeutic applications in a variety ofdermatological disorders including striae distensaeAim of work: To compare the efficacy and safety of fractional CO2 laser combined withintradermal injection of autologous PRP to fractional CO2 laser alone in treatment of striaedistensae.Patient and Methods: Twenty female patients with skin types III-IV with striae distensaewere enrolled in this study. In each patient, two areas were randomly assigned to receivetreatment by either fractional CO2 laser alone (area A) or combined fractional CO2 laser andPRP (area B). All patients were subjected to 4 laser sessions with 4 weeks interval and afollow up period of 4 months after the last session. A biopsy was taken before treatment froma randomly chosen area and two biopsies were taken from each treatment area 2 months afterthe last laser session. Clinical evaluation was done by assessing the percentage of reductionof widest striae after treatment in both areas, as well as patients’ satisfaction score andblinded physician score. Histological evaluation was done by assessing the area % ofcollagen and elastin before and after treatment in both areas using image analysis.Results: There was a statistically significant clinical and histological improvement in bothareas. The clinical improvement of the striae in area B was better than that in area A and thedifference was statistically significant. Regarding the histological improvement, the percentof increase in area % of collagen was found to be higher in area B than area A, however thedifference between both areas was not statistically significant. Area% of elastin was foundsignificantly decreased in both areas. In both areas, there was low incidence (11%) of postinflammatory hyperpigmentation, with no statistically significant difference them.Conclusion: Intradermal injection of autologous PRP is a potentially effective adjuvanttherapy to fractional CO2 laser in treatment of striae distensae.