Flavonols are a class of flavonoids that play a crucial role in plant growth and stress resistance, and are important dietary components in horticultural crops due to their health benefits. Recent research has focused on the transcriptional regulation of flavonol biosynthesis in plants, including the characterization of transcription factors (TFs) and microRNAs (miRNAs), as well as the elucidation of direct and cascade transcriptional mechanisms. Direct regulation involves TFs such as MYB, AP2/ERF, and WRKY, which target key genes in the flavonoid biosynthesis pathway. Cascade regulation includes miRNAs targeting TFs, interactions between activators and repressors, and degradation of these proteins by environmental signals like UV-B or plant hormones. These mechanisms allow plants to fine-tune flavonol homeostasis, balancing growth and stress responses. Molecular design strategies are being applied to breed horticultural crops with high flavonol content and health benefits. Flavonol biosynthesis in plants involves a series of enzymatic reactions starting with phenylalanine, leading to the production of flavonol aglycones such as kaempferol, quercetin, and myricetin. These aglycones are further modified by enzymes like UGT, OMT, and AT to form various flavonol derivatives. Transcriptional regulation of this pathway is mediated by TFs such as R2R3-MYB, WRKY, and bZIP, which control gene expression in response to environmental signals. For example, R2R3-MYB TFs like SG7 and SG19 regulate flavonol biosynthesis by activating key genes. WRKY TFs also play a role in regulating flavonol biosynthesis, while bZIP TFs such as HY5 are involved in UV-B responses. UV-B radiation and plant hormones like jasmonates, auxin, gibberellic acid, and abscisic acid regulate flavonol biosynthesis through complex transcriptional and post-transcriptional mechanisms. These signals influence the expression of TFs and miRNAs, which in turn affect the biosynthesis of flavonols. The regulation of flavonol biosynthesis is essential for plant growth, stress resistance, and the health benefits of horticultural crops. Further research is needed to fully understand these mechanisms and to develop strategies for improving flavonol content in crops.Flavonols are a class of flavonoids that play a crucial role in plant growth and stress resistance, and are important dietary components in horticultural crops due to their health benefits. Recent research has focused on the transcriptional regulation of flavonol biosynthesis in plants, including the characterization of transcription factors (TFs) and microRNAs (miRNAs), as well as the elucidation of direct and cascade transcriptional mechanisms. Direct regulation involves TFs such as MYB, AP2/ERF, and WRKY, which target key genes in the flavonoid biosynthesis pathway. Cascade regulation includes miRNAs targeting TFs, interactions between activators and repressors, and degradation of these proteins by environmental signals like UV-B or plant hormones. These mechanisms allow plants to fine-tune flavonol homeostasis, balancing growth and stress responses. Molecular design strategies are being applied to breed horticultural crops with high flavonol content and health benefits. Flavonol biosynthesis in plants involves a series of enzymatic reactions starting with phenylalanine, leading to the production of flavonol aglycones such as kaempferol, quercetin, and myricetin. These aglycones are further modified by enzymes like UGT, OMT, and AT to form various flavonol derivatives. Transcriptional regulation of this pathway is mediated by TFs such as R2R3-MYB, WRKY, and bZIP, which control gene expression in response to environmental signals. For example, R2R3-MYB TFs like SG7 and SG19 regulate flavonol biosynthesis by activating key genes. WRKY TFs also play a role in regulating flavonol biosynthesis, while bZIP TFs such as HY5 are involved in UV-B responses. UV-B radiation and plant hormones like jasmonates, auxin, gibberellic acid, and abscisic acid regulate flavonol biosynthesis through complex transcriptional and post-transcriptional mechanisms. These signals influence the expression of TFs and miRNAs, which in turn affect the biosynthesis of flavonols. The regulation of flavonol biosynthesis is essential for plant growth, stress resistance, and the health benefits of horticultural crops. Further research is needed to fully understand these mechanisms and to develop strategies for improving flavonol content in crops.