Objective To investigate the correlation between T cell subsets and HCV viralload in HCV infection. Methods Flow cytometry was used to detect peripheral T cell subsets count of 69 patients with hepatitis C and 20 cases of normal health human, and fluorescent quantitative PCR was used to detect viral load in patients with hepa-titis C. Results ① The study showed that the percentage ratio of CD4 +T cells (42.87 ±6.11) and of CD4 +/CD8 +(1.34±0.25) in patients patients was significantly lower than those of normal health group,it was 49.55±6.68 and 1.82±0.11 (P<0.01);but the percentage ratio of CD8 +T cells (32.78±5.48) was higher than that of the normal health human ( 27.35 ±4.32 ) ( P<0.01 ) . There were no significant differences between the two groups in the percentage ratio of CD3 + T cells. ② The viral load gradually increased as the percentage ratio of CD8 +T cells increased, while the percentage ratio of CD4 +T cells and the percentage ratio of CD4 +T cells and CD4 +/ CD8 + were decreased gradually. Conclusion It may be one of the important reasons as the chronic infec-tion of hepatitis C virus by change of T cell subsets, and may be an important cause leading to the decrease of T lymphocyte response ability as the expression level of HCV RNA increases.