Abstract: In recent years，cancer stem cells theory and study attracted people's attention. The theory that the cancer stem cells are the root causes of malignant tumors occurrence，resistance，recurrence and metastasis，and lead to targeted cancer treatment failure eventually being difficult to cure. The biggest obstacle to the treatment of ovarian cancer is the the emergence of drug resistance of tumor cells. It has the great significance for cancer stem cell research to solve the high-malignant tumors such as ovarian cancer drug
resistance and relapse problems. At present，ovarian cancer stem cells have been successfully isolated and identificated，however, the research on the ovarian cancer stem cells is still in the primary stage. This paper provides an overview of the characteristics and isolation and identification methods of ovarian cancer stem cells from the perspective of cancer stem cells.

Key words: Cancer stem cells, Ovarian cancer, SP, Flow cytometry