Objective：To investigate effects of mature dendritic cells（DCs）on mouse liver ischemia/reperfusion（I/R）injury. Methods：After different treatment of bone marrow-derived dendritic cells collected，staining was performed according to the reagent protocol，and the relevant indexes were detected on the cell flow meter（CD40，CD80，CD86，and MHCⅡ）. A total of 20 healthy male C57BL/6 mice were randomly divided into four main experimental groups（n=5 each），including the ischemia/reperfusion（I/R）group，the NEG-BMDCs pretreatment group，the CON-BMDCs pretreatment group，and the H/R-BMDCs pretreatment group. We chose a nonfatal model of 70% liver I/R（treated with 1 h ischemia，and then 6 h reperfusion）. The mice of I/R group were injected with PBS，the NEG-BMDCs pretreatment group with NEG-BMDCs，the CON-BMDCs pretreatment group with CON-BMDCs，the H/R-BMDCs pretreatment group with H/R-BMDCs，at 1 h before operation. The levels of alanine aminotransferase（ALT），aspartate aminotransferase（AST），interleukin-10（IL-10），interleukin-17（IL-17）in serum were detected by enzyme-linked immunosorbent assay（ELISA）. The mRNA expression of TGF-β，FOXP3，IL-10，IL-17 were examined by reverse transcription-polymerase chain reaction（RT-PCR）. Histological haema（HE）stained sections were histopathologically examined using light microscopy. Results：The liver enzyme level were significantly decreased in the H/R-BMDCs pretreatment group，compared to those in the other groups（P < 0.05）. Morphometric analysis and Suzuki’s scores showed that H/R BMDCs improved liver ischemia/reperfusion injury（IRI）to a greater extent than BMDCs from the negative and control groups. The expressions of IL-10 of liver tissue blood serum and liver tissue were upregulated and the expressions of TGF-β and FOXP3 of liver tissue were upregulated in the H/R-BMDCs pretreatment group，while the expression of IL-17 was downregulated in the H/R-BMDCs pretreatment group. Conclusion：Pretreatment with H/R-BMDCs protects mouse from I/R injury by modulating the balance between Treg and Th17 cells.