Objective:To investigate the long-term clinical value of composite biomaterial mesh in inguinal hernia repair.Methods:The prospective randomized controlled non-inferiority study was conducted. The clinical data of 172 adult patients with inguinal hernia who were admitted to 3 medical centers, including Huadong Hospital Affiliated to Fudan University et al, from July 2014 to February 2015 were selected. Based on random number table, patients were divided into two groups. Patients underwent technique of abdominal wall reinforcement with biological mesh. Patients using the electrospun composite biomaterial mesh were allocated into experimental group, and patients using the small intestinal submucosa mesh were allocated into control group. Observation indicators: (1) grouping situations of the enrolled patients; (2) endpoint of the study. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the independent sample t test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test or Fisher exact probability. Comparison of ordinal data was conducted using the non-parameter rank sum test. Taking the recurrence rate of hernia at 6 years after surgery as the basis of efficacy evaluation, the Cochran-Mantel-Haenszel test was used for comparison between groups. The confidence interval method was used to conduct non-inferiority statistical analysis. If the lower limit of 95% confidence interval of the difference of recurrence rate of hernia between the experiment group and the control group was more than -10%, the experiment group was considered to be non-inferior to the control group. If the lower limit of 95% confidence interval is more than 0, the experiment group was considered to be superior to the control group. Results:(1) Grouping situations of the enrolled patients. A total of 172 adult patients with inguinal hernia were selected for eligibility. They were males, aged (61±2)years. All 172 patients were randomly divided into to the experimental group and the control group with 86 cases in each group. At 6 years after surgery, 20 patients in the experi-mental group and 19 patients in the control group was lost to follow-up. (2) Endpoint of the study. ① The primary endpoint of study. At 6 years after surgery, no patient had recurrence in the 66 patients of experimental group and 4 patients had recurrence in the 67 patients of control group. Results of non-inferiority statistical analysis showed that the 95% confidence interval of the difference of recurrence rate of hernia between the two groups was 0.27% to 14.41%, with the lower limit as 0.27%, which was more than -10% and simultaneously more than 0. ② The secondary endpoint of study. There was no significant difference in the simple verbal scale between the two groups after 6 months and 6 years at rest or cough status ( P>0.05). At a follow-up of 6 months after surgery, 2 cases of the experimental group and 5 patients of the control group had complications, showing no significant difference between the two groups( χ2=1.38, P>0.05). At a follow-up of 6 years after surgery, no complication occurred in either group. Conclusion:Composite biological mesh in inguinal repair is safe and feasible, which can have low long-term recurrence and achieve good long-term efficacy.