Abstract: It is believed that cancer stem cells (CSCs) are the cancerous root of tumors that deeply hide in the microenvironment， and the primary origin of the tumor recurrence and metastasis. Characteristics of niche sealing and retention of the CSCs are different from that of the normal stem cells. CSCs are located in the most deficient site of the caner microenvironment with deficiency of vital qi. The niche that storing CSCs is characterized by root deficiency accompanied by blood stasis and phlegm stagnation. CSCs are caused by dislocated ministerial fire which enervates the primitive qi deficiency become more deficient， and deepens the cancer toxin. It is suggested that intervening CSCs and the niche that for CSCs survival by strengthening the vital qi， mitigating the deficiency and stasis of the microenvironment may be an effective strategy to remove the cancer toxin root.