Plasmodium vivaxDuffy Binding Protein region II (PvDBPII) is a leading vaccine candidate against blood-stage vivax malaria. Anti-PvDBPII antibodies potentially block parasite invasion by inhibition of erythrocyte binding. However, knowledge of PvDBPII-specific T cell responses is limited. Here, to assess the responses of PvDBPII-specific CD4+T cells in naturalP. vivaxinfection, three cross-sectional studies were conducted in recovered subjects. In silico analysis was used for potential T cell epitope prediction and selection. PBMCs fromP. vivaxsubjects were stimulated with selected peptides and examined for cytokine production by ELISPOT or intracellular cytokine staining. Six dominant T cell epitopes were identified. Peptide-driven T cell responses showed effector memory CD4+T cell phenotype, secreting both IFN-γ and TNF-α cytokines. Single amino acid substitutions in three T cell epitopes altered levels of IFN-γ memory T cell responses. Seropositivity of anti-PvDBPII antibodies were detected during acute malaria (62%) and persisted up to 12 months (11%) followingP. vivaxinfection. Further correlation analysis showed four out of eighteen subjects had positive antibody and CD4+T cell responses to PvDBPII. Altogether, PvDBPII-specific CD4+T cells were developed in naturalP. vivaxinfections. Data on their antigenicity could facilitate development of an efficacious vivax malaria vaccine.