Objective To evaluate the biomechanical properties of fibroblasts for rabbit experimental myopia after Posterior Scleral Reinforcement (PSR) treatment, and discuss the mechanism of PSR in myopia treatment as viewed from biomechanics. Method 45 rabbits of threeweekold were randomly monocular treated by eyelid suture to prepare experimental myopia eye. After 60 days, the experimental myopia eyes were divided into two groups randomly. Group A was treated by PSR. Group B was treated by similar operation without placing reinforce strap. After three months and six month, the fibroblasts from each group were isolated and cultured in vitro respectively. The cultured cells were then determined to be fibroblasts by using immunocyte chemistry method. Micropipette aspiration technique was used to investigate the viscoelastic properties of the fibroblasts from each group with mechanical model of semiinfinite somatic cells. ResultsThree months after operation, the viscoelastic properties of the scleral fibroblasts in Group A and Group B exhibit no significant difference (P>0.05) three months and six months as well (P>0.05) after operation with the equilibrium modulus, E∞, and apparent viscosity, μ of the scleral fibroblasts in Group A (E = (361.2± 121.1)Pa、μ=(2928.2±669.4)Pa·s) compared with that in Group B (E =(347.6± 82.1)Pa、μ=(2820.6± 593.5)Pa·s). Neither in Group A nor Group B, the E∞ and μ at different stages after operation have significant difference (P>0.05). The E∞ and μ in transition zone tissues at different stages after operation have no significant difference(P>0.05) either. Conclusions The enhancement of PSR is caused by transition zone tissues and the strip itself.