The Cancer miRNA Census (CMC) is a list of 165 cancer-related miRNA genes developed to serve as a reference for miRNA studies in cancer. The list is based on a scoring system incorporating various types of evidence, including miRNA-cancer associations from databases, miRNA associations with cancer hallmarks, and genetic evidence for positive selection of cancer-related mutations. The CMC includes well-validated miRNA genes such as MIR21, MIR155, MIR15A, MIR17, and MIRLET7s, which are known to play important roles in cancer. The list was validated through multiple methods, including comparison with other cancer data, enrichment analysis of biological pathways, and leave-one-out analysis to assess the reliability of the criteria used. The CMC has been shown to be strongly associated with cancer-related processes, making it a useful reference for miRNA gene studies. The CMC miRNA genes were classified as potential oncogenes or tumor suppressors based on their association directions and expression changes in cancer. The CMC is also validated by its association with known cancer-related miRNA genes and its enrichment in cancer-related biological processes. The CMC provides a comprehensive and reliable list of cancer-related miRNA genes that can be used for further research and analysis.The Cancer miRNA Census (CMC) is a list of 165 cancer-related miRNA genes developed to serve as a reference for miRNA studies in cancer. The list is based on a scoring system incorporating various types of evidence, including miRNA-cancer associations from databases, miRNA associations with cancer hallmarks, and genetic evidence for positive selection of cancer-related mutations. The CMC includes well-validated miRNA genes such as MIR21, MIR155, MIR15A, MIR17, and MIRLET7s, which are known to play important roles in cancer. The list was validated through multiple methods, including comparison with other cancer data, enrichment analysis of biological pathways, and leave-one-out analysis to assess the reliability of the criteria used. The CMC has been shown to be strongly associated with cancer-related processes, making it a useful reference for miRNA gene studies. The CMC miRNA genes were classified as potential oncogenes or tumor suppressors based on their association directions and expression changes in cancer. The CMC is also validated by its association with known cancer-related miRNA genes and its enrichment in cancer-related biological processes. The CMC provides a comprehensive and reliable list of cancer-related miRNA genes that can be used for further research and analysis.