Objective To investigate and compare the corneal biomechanical properties obtained by inflating the corneal anterior surface and posterior surface.Methods In this experimental study.Eight Japanese white rabbits were included.One eye was randomly selected from each rabbit and was subjected to anterior pressure in an inflation test rig (anterior surface pressuring eyes group,n=8),and the contralateral eye was subjected to posterior pressure (posterior surface pressuring eyes group,n=8).The pressure range was 1.1-44.0 mmHg.Corneal apical displacement was recorded,then the shell theory was used to deduce the stress-strain relationship,tangent elastic modulus and hysteresis.Corneal thickness,diameter and intraocular pressure (IOP) were measured before the inflation test.A paired t test was used to analyze and compare corneal thickness,diameter,IOP,tangent elastic modulus and hysteresis values.Results Differences in the average corneal thickness,diameter and IOP were not statistically significant between the two groups (thickness:t=-0.073,P＞0.05;diameter:t=0.260,P＞0.05; IOP:t=-1.033,P＞0.05).Corneas tested under posterior pressure displayed significantly higher stiffness than those inflated by anterior pressure (t=6.664,6.681,6.931,P＜0.01).The hysteresis values of the anterior surface pressuring eyes group were significantly greater than those of the posterior surface pressuring eyes,the values were 2.50×10-4 MPa and 1.94×10-4 MPa,respectively.The difference was statistically significant (t=-2.891,P＜0.05).Conclusion Corneal specimens inflated posteriorly were significantly stiffer than those inflated anteriorly.As a nonlinear viscoelastic tissue,the cornea not only presented region-associated stiff asymmetry in the coronal plane,but also presented stiff asymmetry in the sagittal plane.The experimental results could have an reference value in correcting IOP readings in the future.