ObjectiveTo analyze the effect of a new type of tension-reduced suture named “double W tension-reduced suture technique” on the abdominal scars following the da Vinci robot-assisted gastrectomy for severely obese patients.Methods40 abdominal incisions following the da Vinci robot-assisted gastrectomy on severely obese patients from September 1st, 2021 to March 1st, 2022 were comprised in the study. 20 incisions were closed by the conventional full-thickness surgical suture as the control group, and 20 incisions were sewn up by double W tension-reduced suture as the double W group. The scars were assessed at the 1-month follow-up visit using the Vancouver scar scale (VSS), ultrasound and patient satisfaction. Meanwhile, digital photographs of scars were taken as well.ResultsThe VSS score was 6.80 ± 2.16 in the control group, while that of the double W group was 2.60 ± 1.89. The difference between groups was significant. Digital photographs showed that the scar color was not only light and close to the skin color, but also flat and soft in the double W group. Ultrasound showed that the fibers of subcutaneous tissue in the double W group were arranged neatly, the ultrasonic signal intensity was relatively uniform, and the tunnel was small without obvious lacunae. More patients were satisfied and very satisfied with scars in the double W group.ConclusionDouble W tension-reduced suture technique could significantly improve the appearance and reduce comorbidities of scars following the da Vinci robot-assisted gastrectomy for severely obese patients.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12893-023-01979-8.