Objective To explore the effect of TLR2 on collagen Ⅰ(colⅠ) in adipose tissue of high-fat-diet induced obese mice.Methods Male C57bl/6J mice and TLR2 knockout mice were divided into groups according to high fat diet or normal chow.Total collagen, TLR2, colⅠ, MMP1, MMP2, TIMP1, colⅠα1 mRNA and colⅠα2 mRNA in adipose tissue were measured at the end of the experiments.Results Total collagen, TLR2, colⅠ, MMP2, TIMP1, colⅠα1 mRNA, and colⅠα2 mRNA in adipose tissue increased while MMP1 in adipose tissue decreased in mice with high fat diet.Decreased levels of total collagen, colⅠ, MMP2, TIMP1, colⅠα1 mRNA and colⅠα2 mRNA in adipose tissue were detected in TLR2 gene knockout mice with high fat diet.However, there was an increased level of MMP1 in TLR2 gene knockout mice with high fat diet.Conclusion In high-fat-diet induced obese mice, deposition of colⅠ in adipose tissue seems to be alleviated by TLR2 gene knockout via MMP1 and TIMP1.