Objective To explore the research progress in molecular mechanisms, clinical diagnosis and treatment of single cell sequencing (SCS) techniques in the progression of colorectal cancer liver metastasis (CRLM). Method The literatures on SCS in CRLM at home and abroad in recent years were reviewed. Results SCS technology could perform high-throughput sequencing on the genetic information of different cell subsets at the single-cell level, which was helpful to explore the molecular mechanism of action in the occurrence, development, metastasis, immune escape and drug resistance of colorectal cancer liver metastasis. Thus making the clinical diagnosis, treatment, and prognosis of colorectal cancer more accurate. Conclusion SCS technology, as an emerging sequencing technology, can provide us with updated ideas and more perspectives to explore the occurrence and development of tumors and the prevention and treatment of tumors.