Objective:To explore the changes in tongue color, blood flow of tongue microcirculation and ICAM-1 in rats with type 2 diabetes mellitus. MethodsExcept for the 10 rats in the normal group, the other Wistar rats were used to establish the model of type 2 diabetes mellitus. Rats for successful modelling were randomly assigned into model group and inhibitor group, 10 rats in each group. In the inhibitor group, PDTC, the inhibitor of the NF-κB signaling pathway was intraperitoneally injected for 8 weeks. The tongue images of diabetic rats were collected and analyzed using “small TDA-1 tongue imager” and “tongue digital analysis system (TDAS)”. The changes of hemodynamics in tongue microcirculation of diabetic rats were observed by laser Doppler flowmetry. The concentrations of ICAM-1 in serum, tongue tissue and liver tissue were observed by ELISA.  Results:In comparison of objective indicators of tongue images, it was shown that compared with the normal group, zhiClrI and taiClrI (the quantitative indicators of tongue color) were significantly reduced, while zhiClrS and taiClrS (the quantitative indicators of tongue color) were significantly increased in the model group and the inhibitor group (P<0.05). Compared with the model group, zhiClrS (the quantitative indicator of tongue color) was reduced in the inhibitor group (P<0.05). In comparison of local hemodynamics of the tongue, it was shown that compared with the normal group, mean perfusion area of blood flow in local tongue microcirculation decreased significantly in the normal group and the inhibitor group (P<0.05). In comparison of adhesion factor, it was shown that compared with the normal group, the concentration of serum adhesion factor ICAM-1 increased (P<0.05) and the concentration of ICAM-1 in tongue tissue and liver tissue was significantly increased (P<0.01) in the model group. Compared with the model group, the concentration of ICAM-1 in tongue tissue and liver tissue was significantly reduced in the inhibitor group (P<0.01).  Conclusion:The changes of tongue color in rats with type 2 diabetes mellitus may be related to disorder of local microcirculation of the tongue and increase of the adhesion factor ICAM-1.