Despite its reliability, radial forearm (RF) flap is still affected by high donor site morbidity with poor cosmetic and functional outcomes after coverage with skin grafts. Having fat grafting demonstrated promising and effective filling and rejuvenating properties, we considered and tested it as a valuable alternative to dermal substitutes for the aesthetic improvement of RF flap donor site. Thirty-three patients with previous RF free flap reconstruction and poor donor site outcomes after full-thickness skin grafting to RF region were evaluated for secondary fat injection to improve outcomes. Objective and subjective assessments of results with standardized ultrasonographic soft tissue thickness measurements, cutaneous sensibility tests with the pressure-specified sensory device and scar assessment scale (POSAS) have been performed. Bivariate statistical analyses were performed comparing outcomes with contralateral healthy forearm. All cases showed significant improvement in soft tissue thickness (p< 0.031), cutaneous sensibility and scar appearance, with improved patient's and observers' scar assessment scores (<0.001). In conclusion, fat transplantation is an effective procedure that provided us with an adjunctive autologous layer in-between skin graft and underlying fascia, as well as a rejuvenating effect on skin and scars.