Abstract: Objective To detect the frequency of CD4⁺T,CD8⁺ T,CD4⁺CD25^-T,CD4⁺CD25⁺T cells in nasopharyngeal carcinoma (NPC), and to explore the objective clinical index to evaluate the immunity of NPC. Methods Flow Cytometry was to calculate the frequency of CD4⁺T,CD8⁺T,CD4⁺CD25-T,CD4⁺CD25⁺T cells in tumor tissue and peripheral blood from forty NPC and ten control. Results The proportion of CD4⁺T cells and ratio of CD4⁺/CD8⁺in NPC are significantly lower than those in control group（P<0.05）,but there was no difference in CD8⁺T cells between two groups（P>0.05）,there was also no significant difference in CD4⁺/CD8⁺between tumor tissue and peripheral blood in NPC（P>0.05）. The ratios of CD4⁺CD25⁺T cells in tissue and peripheral blood of NPC was higher than control group, and the ratio in tumor tissue was dramatically higher than in peripheral blood in NPC（P<0.05）.There was negative correlation between CD4⁺CD25⁺T cells and CD8⁺,CD4⁺CD25-T cells in tumor tissue of NPC respectively（r=-0.70，-0.675,P<0.05）,but this was not seen in peripheral blood （P>0.05）.According to the tumor sizes, patients with NPC were divided into four groups. The ratio of CD4⁺CD25⁺T cells in T4 tissue was higher than that in T1,T2,T3 respectively（P<0.05）,but there was no difference among T1,T2,T3 groups（P>0.05）.There was no correlation between frequency of CD4⁺CD25⁺T cells and lymphonode metastasis（P>0.05）.The ratio of CD4⁺CD25⁺T cells in tumor tissue at stage Ⅲ+Ⅳ was higher than the stage Ⅰ+Ⅱ of NPC（P<0.05）,but there was no difference between the two stage in peripheral blood in NP（P>0.05). Conclusion CD4⁺CD25⁺T cells was not correlated to the NPC prognosis, but detection of CD4⁺CD25⁺T cells in tissue and peripheral blood in NPC joint the ratio of CD4⁺/CD8⁺ which was used in the past will all-round evaluate the immunity of NPC, It may provide evidence for clinical therapy.