ObjectiveTo establish the model about concanavalin Ainduced（Con A）experimental liver injury in mice. MethodsForty Balb/C mice were randomly divided into 4 groups(ten for each group), A, B, C and D. Con A 10mg/kg, 20mg/kg or 30mg/kg was intravenously (tail vein) injected into the mice in group A, B and C respectively while normal saline was used for the group D (control group). Activity of alanine transaminase(ALT), death rate  and liver histopathological changes were observed after 8 hours of injection. The optimal Con A dose (20mg/kg) was selected, activity of ALT, death rate  and liver histopathological changes were observed based on such dosage. ResultsAfter 8 hours of injection of Con A, no dead mouse was found in group A and D, but 3 and 10 mice were dead in group B and C respectively; the ALT level in group A and B was (215.55±70.19) IU /L and  (2 516.14±764.69) IU / L respectively, both were significantly higher than (57.30±12.21) IU /L in group D (t=-8.466, t=-10.143, respectively; both P=0.000). Liver  histopathology showed only degeneration of liver cells was present in group A, while degeneration, necrosis and liver inflammatory cells infiltration in group B and C. Within 24 hours of injection of 20mg/kg of Con A, the death rate, activity of ALT, liver inflammatory cells infiltration, hepatocyte degeneration and  necrosis  exacerbated with the prolongation of time. ConclusionThe optimal dosage to establish Con Ainduced experimental liver injury in mice is 20mg/kg, with the optimal observation time at 8 hours after intravenous (tail vein) injected.