BnSIP1-1is the first identified SIP1 (6b Interacting Protein1) subfamily gene of the trihelix transcription factor family fromBrassica napus (B. napus).We previously used a reverse genetic method to reveal its abiotic stress response function in endowing plants resistance to drought and salinity, as well as ABA (Abscisic acid). However, the molecular mechanisms ofBnSIP1-1are unclear. In this study, the global transcriptome files ofBnSIP1-1-overexpressing transgenic and wildtypeB. napusseedlings under ABA treatment were constructed using RNA-seq. A total of 1823 and 5512 DEGs (Differentially Expressed Genes) were identified in OE vs. WT and OE_ABA vs. WT_ABA comparison groups, which included 751 and 2567 up-regulated DEGs, and 1072 and 2945 down-regulated DEGs, separately. The impact of overexpressedBnSIP1-1on plants was amplified by ABA, indicatingBnSIP1-1was an ABA-conditioned responsive gene. More interestingly, we found the reasons forBnSIP1-1increasing plants’ insensitivity to ABA were not by regulating ABA synthesis and catabolism, but by manipulating ABA transportation, ABA signal perception and transduction, inositol phosphate metabolism, as well as endomembrane trafficking, indirectly suggesting this gene may play roles upstream of the core ABA response pathway. Our results provided new insights into improving the knowledge about the function ofBnSIP1-1and the ABA signaling mechanism inB. napus.