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The plant-specific ASR (abscisic acid, stress and ripening) transcription factors are pivotal regulators of plant responses to abiotic stresses. However, their functions in plant disease resistance remain largely unknown. In this study, we revealed the role of OsASR6 in rice plants’ resistance to two important bacterial diseases caused by <i>Xanthomonas</i> <i>oryzae</i> pv. <i>oryzae</i> (<i>Xoo</i>) and <i>X.</i> <i>oryzae</i> pv. <i>oryzicola</i> (<i>Xoc</i>) and elucidated the mechanisms underlying OsASR6-regulated resistance. The expression of <i>OsASR6</i> was strongly elevated in response to both <i>Xoo</i> and <i>Xoc</i> challenges. Silencing of <i>OsASR6</i> in OsASR6-RNAi transgenic plants markedly enhanced rice resistance to the two bacterial pathogens. Moreover, comparative transcriptome analyses for OsASR6-RNAi and wild-type plants inoculated and uninoculated with <i>Xoc</i> demonstrated that <i>OsASR6</i> suppressed rice resistance to <i>Xoc</i> by comprehensively fine-tuning <i>CIPK15</i>- and <i>WRKY45-1</i>-mediated immunity, SA signaling and redox homeostasis. Further luciferase reporter assays confirmed that OsASR6 negatively regulated <i>CIPK15</i> but not <i>WRKY45-1</i> expression in planta. Overexpression of <i>OsCIPK15</i> strongly enhanced rice resistance to <i>Xoo</i> and <i>Xoc</i>. Collectively, these results reveal that OsASR6 alleviates rice resistance through the transcriptional suppression of <i>OsCIPK15</i>, and thus links calcium signaling to rice resistance against <i>X.</i> <i>oryzae</i>. Our findings provide insight into the mechanisms underlying OsASR6-mediated regulation of rice resistance to <i>X.</i> <i>oryzae</i>.