Objective To explore the evaluation value of T lymphocyte subgroup levels on the prognosis and recurrence of primary genital herpes.Methods A total of 110 patients with primary genital herpes admitted to our hospital from January 2021 to January 2024 were selected. Based on whether there was a recurrence within one year of follow-up, patients were divided into a non-recurrence group (n = 85) and a recurrence group (n = 25), and according to the prognosis, into a good prognosis group (n = 78) and a poor prognosis group (n = 32). The levels of T lymphocyte subgroups were compared between these groups. Logistic analysis was used to identify the factors influencing the recurrence of primary genital herpes and to construct nomograms. Spearman's analysis was used to explore the correlation between various indicators. Receiver operating characteristic (ROC) curves were constructed to analyze the predictive efficiency of recurrence and prognosis in patients with primary genital herpes.Results The levels of CD3⁺ and CD4⁺ in the recurrence group were lower than those in the non-recurrence group, and CD8⁺ was higher than that in the non-recurrence group (P < 0.05). The levels of CD3⁺ and CD4⁺ in the poor prognosis group were lower than those in the good prognosis group, and CD8⁺ was higher than that in the good prognosis group (P < 0.05). Low CD3⁺ levels[O^R = 0.878 (95% CI: 0.774, 0.996)], low CD4⁺ levels [O^R = 0.860 (95% CI: 0.744, 0.994) ], and high CD8⁺ levels [O^R = 1.833 (95% CI: 1.337, 2.512) ] were identified as risk factors for the recurrence of primary genital herpes (P < 0.05). Spearman correlation analysis showed that in patients with poor prognosis of primary genital herpes, CD4⁺ levels were positively correlated with CD3⁺ levels (r_s = 0.434, P =0.019), while CD8⁺ levels were negatively correlated with CD3⁺ levels (r_s = -0.376, P =0.044). ROC curve analysis demonstrated that the combined prediction of CD3⁺, CD4⁺, and CD8⁺ for the recurrence and poor prognosis of primary genital herpes had significantly higher AUC values [sensitivity: 95.7% (95% CI: 0.796, 0.999), specificity: 80.5% (95% CI: 0.699, 0.879); sensitivity: 93.1% (95% CI: 0.792, 0.992), specificity: 93.0% (95% CI: 0.857, 0.979) ] compared to the individual prediction of CD3⁺, CD4⁺, or CD8?.Conclusion T lymphocyte subgroup levels have a good predictive value for the prognosis and recurrence of primary genital herpes.