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Abscisic acid-responsive element-binding factor 1 (<i>ABF1</i>), a key transcription factor in the ABA signal transduction process, regulates the expression of downstream ABA-responsive genes and is involved in modulating plant responses to abiotic stress and developmental processes. However, there is currently limited research on the feedback regulation of <i>ABF1</i> in ABA signaling. This study delves into the function of <i>BcABF1</i> in Pakchoi. We observed a marked increase in <i>BcABF1</i> expression in leaves upon ABA induction. The overexpression of <i>BcABF1</i> not only spurred <i>Arabidopsis</i> growth but also augmented the levels of endogenous IAA. Furthermore, <i>BcABF1</i> overexpression in <i>Arabidopsis</i> significantly decreased leaf water loss and enhanced the expression of genes associated with drought tolerance in the ABA pathway. Intriguingly, we found that BcABF1 can directly activate <i>BcPYL4</i> expression, a critical receptor in the ABA pathway. Similar to <i>BcABF1</i>, the overexpression of <i>BcPYL4</i> in <i>Arabidopsis</i> also reduces leaf water loss and promotes the expression of drought and other ABA-responsive genes. Finally, our findings suggested a novel feedback regulation mechanism within the ABA signaling pathway, wherein BcABF1 positively amplifies the ABA signal by directly binding to and activating the <i>BcPYL4</i> promoter.