Objective To investigate how to develop a rabbit model for corneal ectasia in vitro with collagenase type II. Methods In this experimental study, 20 postmortem New Zealand white rabbit corneas were randomly divided into 4 groups: group I (the control group with 15% dextran), group II (5 mg/ml collagenase type II with 15% dextran), group III (10 mg/ml collagenase type II with 15% dextran) and group IV (15 mg/ml collagenase type II with 15% dextran). After epithelial debridement, corneas were mounted and pressed onto artificial anterior chambers and different kinds of solutions were applied to the corneas for 60 minutes. The average corneal curvature and central corneal thickness were measured before and after collagenase exposure at different intraocular pressure (IOP) levels (15 mmHg, 30 mmHg, 45 mmHg). Corneal specimens were processed for light microscopy with HE staining. Changes in average corneal curvature and central corneal thickness were analyzed statistically by one-way ANOVA in SPSS 17.0. Results After collagenase exposure, significant changes in △Km (F=8.46, 9.24, 8.58, P＜0.01) were seen among groups at 15 mmHg, 30 mmHg and 45 mmHg. A significant increase in △Km was seen in group IV across all IOP levels (P＜0.01) compared to group I, while no significant changes were seen in groups II and III (P＞0.05). No significant changes in △CCT were seen among groups across all IOP levels (F=0.22, 0.66, 1.60, P＞0.05). Light microscopy showed a loss of the normal lamellar structure and changes in collagen organization after collagenase exposure. Conclusion 15 mg/ml collagenase type II can induce a significant increase in average corneal curvature, which might be considered for a method of building the rabbit model for corneal ectasia in vitro.