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Objective Cornea is generally regarded as non-linear elastic material, there may be some errors if one uses linear elastic model to characterize the mechanical properties of the cornea. This study explores the feasibility of using piecewise linear elastic model to describe nonlinear elastic behavior of cornea based on inflation tests. Methods Five fresh rabbit eyes were selected, including the cornea and a narrow ring of surrounding scleral tissue, and mounted on a specially designed test rig that could provide watertight edge fixity for the specimens along their ring of scleral tissue. The specimens were subjected to a gradually increasing posterior pressure caused by a column of saline water to simulate the effect of elevated intraocular pressure. The data related to the applied pressure, the corresponding apical displacement and image information were automatically recorded for later analysis. Using the cornea profile picture we established the real cornea model at the pressure of 7mmHg, 14mmHg and 21mmHg, respectively. Corneal material was considered as a linear elastic material in each pressure range of 7-14mmHg, 14-21mmHg and 21-28mmHg. Using the finite element method we simulated inflation tests for determinating the elastic modulus of the cornea in the above pressure ranges. Results Elastic modulus of rabbit cornea obtained in 7-14mmHg, 14-21mmHg, 21-28mmHg were (0.73±0.16) MPa, (2.20±0.43) MPa and (3.03±0.37) MPa, respectively. This result was consistent with the literature. Conclusions It is feasible to describe approximately nonlinear elastic behavior of cornea by using piecewise linear model.