Objective To investigate the effect of different degrees of wound eversion on scar formation at the donor site of anterolateral thigh flaps by a prospective clinical randomized controlled study. MethodsAccording to the degree of wound eversion, the clinical trial was designed with groups of non-eversion (group A), eversion of 0.5 cm (group B), and eversion of 1.0 cm (group C). Patients who underwent anterolateral femoral flap transplantation between September 2021 and March 2023 were collected as study subjects, and a total of 36 patients were included according to the selection criteria. After resected the anterolateral thigh flaps during operation, the wound at donor site of each patient was divided into two equal incisions, and the random number table method was used to group them (n=24) and perform corresponding treatments. Thirty of these patients completed follow-up and were included in the final study (group A n=18, group B n=23, and group C n=29). There were 26 males and 4 females with a median age of 53 years (range, 35-62 years). The body mass index was 17.88-29.18 kg/m2 (mean, 23.09 kg/m2). There was no significant difference in the age and body mass index between groups (P>0.05). The incision healing and scar quality of three groups were compared, as well as the Patient and Observer Scar Assessment Scale (POSAS) score [including the observer component of the POSAS (OSAS) and the patient component of the POSAS (PSAS)], Vancouver Scar Scale (VSS) score, scar width, and patient satisfaction score [visual analogue scale (VAS) score]. Results In group C, 1 case had poor healing of the incision after operation, which healed after debridement and dressing change; 1 case had incision necrosis at 3 months after operation, which healed by second intention after active dressing change and suturing again. The other incisions in all groups healed by first intention. At 6 months after operation, the PSAS, OSAS, and patient satisfaction scores were the lowest in group B, followed by group A, and the highest in group C. The differences between the groups were significant (P<0.05). There was no significant difference between the groups in the VSS scores and scar widths (P>0.05). ConclusionModerate everted closure may reduce the formation of hypertrophic scars at the incision site of the anterior lateral thigh flap to a certain extent.