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The AT-hook motif nuclear-localized (<i>AHL</i>) family is pivotal for the abiotic stress response in plants. However, the function of the cassava <i>AHL</i> genes has not been elucidated. Promoters, as important regulatory elements of gene expression, play a crucial role in stress resistance. In this study, the promoter of the cassava <i>MeAHL31</i> gene was cloned. The MeAHL31 protein was localized to the cytoplasm and the nucleus. qRT-PCR analysis revealed that the <i>MeAHL31</i> gene was expressed in almost all tissues tested, and the expression in tuber roots was 321.3 times higher than that in petioles. Promoter analysis showed that the <i>MeAHL31</i> promoter contains drought, methyl jasmonate (MeJA), abscisic acid (ABA), and gibberellin (GA) <i>cis</i>-acting elements. Expression analysis indicated that the <i>MeAHL31</i> gene is dramatically affected by treatments with salt, drought, MeJA, ABA, and GA3. Histochemical staining in the <i>proMeAHL31-GUS</i> transgenic <i>Arabidopsis</i> corroborated that the GUS staining was found in most tissues and organs, excluding seeds. Beta-glucuronidase (GUS) activity assays showed that the activities in the <i>proMeAHL31-GUS</i> transgenic <i>Arabidopsis</i> were enhanced by different concentrations of NaCl, mannitol (for simulating drought), and MeJA treatments. The integrated findings suggest that the <i>MeAHL31</i> promoter responds to the abiotic stresses of salt and drought, and its activity is regulated by the MeJA hormone signal.