Objective：This study aims to explore the application value and possible mechanism of monocarboxy transporter 1（MCT1）in the prediction of prognosis for the patients with hepatocellular carcinoma（HCC）. Methods：We selected the tissues of HCC patients after liver resection，and used RT-PCR to estimate the expression of MCT1 and divided the patients into MCT1 high and MCT1 low groups；the phenotype and activation of the immune cells from the peripheral blood as well as the immune statues of the resected liver tissues from both groups were analyzed. A retrospective analysis of the relationship between the overall survival（OS） and disease-free survival（DFS） rate to the expression of lactate or MCT1 between 43 HCC patients who underwent liver surgery was also compared. Results：Although there was no difference in the phenotype of immune cells from peripheral blood，CD4+ T cells were easier to transform into Treg cells under the stimulation of lactic acid in the high MCT1 expression group；under the environment of lactic acid，the Treg cells from the MCT1 high expression group presented a significant increase of metabolism level；MCT1 high expression group had lower immune cell infiltration and up-regulated expression of anti-inflammatory cytokines（Foxp3，CTLA3，IL-10）. The OS and DFS rate were much worse in MCT1 high patients comparing with MCT1 low group. Conclusion：MCT1-Treg related targets may serve as a new target for the diagnosis，therapeutic and prognosis prediction of HCC.