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A finite element model was employed to analyze the microindentation test with a spherical indenter on gelatin films. The deficiency of using elastic-plastic constitutive law to describe indentation response of gelatin film was recognized and a viscoelastic model was proposed for the first time to analyze indentation experiments on polymeric materials. Based on viscoelastic analysis, it was found that gelatin is nonlinear viscoelastic. In addition, modulus in the thickness direction of a gelatin film was determined to be 2.5-2.9 GPa as compared with its tensile modulus of 4.6 GPa in the transverse direction.