Abstract:AIM: To compare multiple visual disc parameters and the retinal morphology of healthy Zhuang adults with healthy Han adults. METHODS: Two equal cohorts of 120 healthy adults (480 eyes) of Zhuang and Han ancestry aged 20 to 60 years from unrelated families residing in Longlin County, Guangxi Zhuang Autonomous Region, China, for at least three generations were enrolled in this study. The visual disc parameters in Zhuang and Han populations were determined in four different age brackets (20-29, 30-39, 40-49, and 50-59) using Heidelberg retinal tomograph-II (HRT-II), and the relations between these parameters and race, gender, eye (left/right), and age were evaluated. The evaluated visual disc parameters included disc area (DA mm2),cup area(CA mm2),cup/disc area ratio(C/DAR), rim/disc area ratio (R/DAR), rim area (RA mm2), height variation contour (HVC mm), cup volume (CV mm3), rim volume (RV mm3), mean cup depth (MCD mm), maximal cup depth (MxCD mm), cup shape measure (CSM mm), mean retinal nerve fiber layer thickness (mRNFLT mm)and retinal nerve fiber layer area(RNFLA mm2). RESULTS: There were significant difference in C/A, C/D, R/D, MCD, and MxCD between the ethnic two populations in the 30-39 year group (P<0.05), and a significant difference in RA between the 50-59 year age groups(P<0.05).No other statistically significant differences were observed for any other parameters. For both Zhuang and Han adults, mRNFLT and RNFLA were negatively correlated with age (correlation coefficients: -0.213 and -0.186 in the Zhuang population, -0.233 and -0.219 in the Han population). No statistical significance in these parameters was observed between males and females or between right and left eyes of the two ethnic populations. The C/DAR ratio difference between the left and right eyes ranged from 0.000 to 0.162 in the Zhuang population and from 0.048 to 0.112 in the Han population. CONCLUSION: There are few significant differences in optic papilla contour parameters between healthy Zhuang and Han adults, except for the 30-39 age group, and there is no statistical difference in these visual disc parameters by gender or eye between the two populations.