Mining gene regulatory networks (GRNs) in cancer can help identify the difference between different phenotypes and reveal the cancerogenesis mechanism. The SCAR_Regulon module provides putative GRNs between transcription factors and their candidate target of cancer single-cell RNA sequencing datasets in the human and mouse. In addition, the GO term enrichment of each regulon and regulatory networks of transcription factors in the datasets are also available to view, promoting the understanding of the gene transcriptional regulation in cancer on the cell type level.