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Brassinosteroid (BR) signaling leads to the nuclear accumulation of the BRASSINAZOLE-RESISTANT 1 (BZR1) transcription factor, which plays dual roles in activating or repressing the expression of thousands of genes. BZR1 represses gene expression by recruiting histone deacetylases, but how it activates transcription of BR-induced genes remains unclear. Here, we show that BR reshapes the genome-wide chromatin accessibility landscape, increasing the accessibility of BR-induced genes and reducing the accessibility of BR-repressed genes in Arabidopsis. BZR1 physically interacts with the BRAHMA-associated SWI/SNF (BAS)-chromatin-remodeling complex on the genome and selectively recruits the BAS complex to BR-activated genes. Depletion of BAS abrogates the capacities of BZR1 to increase chromatin accessibility, activate gene expression, and promote cell elongation without affecting BZR1's ability to reduce chromatin accessibility and expression of BR-repressed genes. Together, these data identify that BZR1 recruits the BAS complex to open chromatin and to mediate BR-induced transcriptional activation of growth-promoting genes. [Display omitted] • Brassinosteroid has dual roles in reshaping the chromatin accessibility landscape • BZR1 physically interacts with the BAS complex • The BAS complex determines BR-induced transcriptional activation • BZR1 recruits the BAS complex for chromatin opening and BR-mediated skotomorphogenesis The mechanism that dictates the transcriptional activation ability of the brassinosteroid (BR) hormone remains largely unclear. Zhu et al. find that the BAS-chromatin-remodeling subcomplexes are major determinants of the transcriptional activation activity of the BR signaling pathway for allowing plants to shape their growth and development trajectory. [ABSTRACT FROM AUTHOR]