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The NAC family of transcription factors (TFs) regulate plant development and abiotic stress. However, the specific function and response mechanism of NAC TFs that increase drought resistance in <i>Picea wilsonii</i> remain largely unknown. In this study, we functionally characterized a member of the PwNAC family known as <i>PwNAC31</i>. PwNAC31 is a nuclear-localized protein with transcriptional activation activity and contains an NAC domain that shows extensive homology with ANAC072 in <i>Arabidopsis</i>. The expression level of <i>PwNAC31</i> is significantly upregulated under drought and ABA treatments. The heterologous expression of <i>PwNAC31</i> in <i>atnac072 Arabidopsis</i> mutants enhances the seed vigor and germination rates and restores the hypersensitive phenotype of <i>atnac072</i> under drought stress, accompanied by the up-regulated expression of drought-responsive genes such as <i>DREB2A (DEHYDRATION-RESPONSIVE ELEMENT BINDING PROTEIN 2A)</i> and <i>ERD1 (EARLY RESPONSIVE TO DEHYDRATION STRESS 1)</i>. Yeast two-hybrid and bimolecular fluorescence complementation assays confirmed that PwNAC31 interacts with DREB2A and ABF3 (ABSCISIC ACID-RESPONSIVE ELEMENT-BINDING FACTOR 3). Yeast one-hybrid and dual-luciferase assays showed that PwNAC31, together with its interaction protein DREB2A, directly regulated the expression of <i>ERD1</i> by binding to the DRE element of the <i>ERD1</i> promoter. Collectively, our study provides evidence that PwNAC31 activates <i>ERD1</i> by interacting with DREB2A to enhance drought tolerance in transgenic <i>Arabidopsis</i>.