Background <p>Trocar-site hernia is an underappreciated condition with estimates of approximately 25% at 2&#xa0;years follow-up. Duramesh™ has emerged as a novel product with potential benefits for incisional hernia prevention. The aim of this trial is to establish if Duramesh is superior to conventional suture for prevention of periumbilical trocar-site hernia following laparoscopic surgery.</p> Methods <p>The TROCAR trial is a prospective single-centre, parallel arm, double-blind randomised controlled trial conducted in the United Kingdom. A total of 250 randomised participants (1:1 ratio) will be allocated to receive either Duramesh or conventional suture (J-vicryl or J-PDS). The primary outcome is the cumulative incidence of sonographically detected periumbilical trocar-site hernia at 2&#xa0;years of the index operation. Secondary outcomes are 90-day surgical site occurrence (SSO), 90-day surgical site infection (SSI), 90-day rate of reoperation, 90-day mortality, length of hospital stay, and quality of life at 3&#xa0;months, 1&#xa0;year and 2&#xa0;years measured using a modified EuraHS-QoL score and modified Carolinas Comfort Scale.</p> Conclusion <p>TROCAR will provide level 1 evidence on trocar-site hernia prevention in both the emergency and elective settings.</p> Trial registration <p>Registration number ISRCTN14473961 (<a href="https://doi.org/10.1186/ISRCTN14473961">https://doi.org/10.1186/ISRCTN14473961</a>). Registered on 14th April 2025.</p>